Call quality drops after ca 15 min

ZoraIsHere

Hi guys,
I have the following issue. My call quality drops after around 15 mins (sometimes only for me sometimes for both of us). Sometimes it also ends the call. At the moment I can only use 2G as my carrier doesn't support VoLTE. With Signal etc there is no issue. Now the funny part starts: I found a lot of people claiming the same issue on the offical Google support forum. I have a Pixel 7a with the latest GOS Version. People write that only a downgrade to android 13 fixes the issue. Unfortunately the thread is closed. Any ideas what I can do?

ZoraIsHere

Any ideas?

lxto77

ZoraIsHere
The latest Version on my Pixel 7a is Andriod 15, GOS 2024111800,
I have no telephone issues here. I have activated "use 4G telephone connections" in sim settings.

nanoq

ZoraIsHere I have no idea but I have had the same issue with an iPhone 15pro. May be it’s a 5G or carrier thing?

ZoraIsHere

First of all: thank you for your answers and sorry for the unstructered initial post. I wrote it from my smartphone which should never happen again. Here are a couple of more facts I found out
It's not carrier related as

I used the same SimCard on an iPhone SE 1. Generation without any issues
My wife has the same carrier with an Pixel 8a without any problems

Also it cannot be hardware related (in my point of view) as I can have long calls with Signal, Threema, etc. without any issues. So in my opinion it must be software related. Also because people wrote in the post, that the issue disappeared, when they did a downgrade to Android 13.
I'm still wondering, why the post is closed when the issue still appears...

de0u

ZoraIsHere I didn't see a post in that Google thread about audio quality in a call being fine for a long time (you indicated 15 minutes) before degrading. Also, a high density of posts in the Google forum thread were from Bulgaria, which I don't think is representative of all Pixel users. Are you in Bulgaria?

Finally, I think i remember that in the spring Google shipped a bug in the IP telephony stack (affecting VoLTE). At the time downgrading would have resolved that, but I believe Google issued a fix, so downgrading should no longer be necessary.

Overall, it isn't clear that what you are experiencing is the same thing as what those users were reporting nine months ago.

Does the call-quality degradation happen wherever you are, or mostly in specific locations? Is it always after more than 10 minutes? When it happens, is the phone unusually warm? If you swap SIM cards with your wife, does the problem move or stay?

ZoraIsHere

de0u Thank you for your answer de0u! Regarding your questions:

No, I'm not from Bulgaria (currently in Portugal)
In the post mentioned, there are also posts from UK, Italy and US
As mentioned, I'm not using VoLTE as its not supported here by my carrier (so I think its not related to the bug you mentioned)
The quall quality drops always after around 15 minutes.
The phone isn't warm
Even when switching the location I have the same issue (I also have full signal strength here)
Switching SimCards didn't solve the issue
Here is another post with the same issue (if you want I can also search for more)

Any ideas?

de0u

ZoraIsHere

The quall quality drops always after around 15 minutes.

[...]

Here is another post with the same issue (if you want I can also search for more)

What I see in that post is "The audio would be completely muted on both ends from time to time during a call. Then the call will drop." In particular, I see "from time to time" and I don't see "15 minutes". Edit: also, "completely muted" and "call quality drops" don't sound like the same thing. I don't see any indication there as to whether VoLTE, 3G, or 2G is being used. Android 14 is mentioned, but that went out more than a year ago. Did your experience of the 15-minutes issue begin a year ago?

There are lots of reports online of people having problems with phone calls. But cellular phone systems are complicated, so many things can go wrong, and two reports of something going wrong aren't very likely to be "the same issue" unless the symptoms are share multiple details.

When you experience in-call audio issues, does it happen both with and without an external headset?

ZoraIsHere

de0u the issue happens with or without a headset. I bought my Pixel in June/July this year so I cannot say how it was in the beginning of the year.

de0u

ZoraIsHere I bought my Pixel in June/July this year so I cannot say how it was in the beginning of the year.

I think it is best to treat the issue you are experiencing as novel rather than being "the same as" call-quality issues that have different and/or unknown features. In particular, if the issue you experience is tightly associated with a call running longer than 15 minutes, then I think only call-quality reports that have a tight association with a specific and long duration should be considered.

Here are some generic suggestions:

The GrapheneOS usage guide recommends: Settings, System, Reset options, Reset Mobile Network settings.
The usage guide also recommends requesting a new SIM card from your carrier. Sometimes they go bad over time.
Borrow a SIM card from a different carrier (or buy a cheap pre-paid card from a convenience store) and see if the 15-minute audio-quality limit applies. Try to get a "genuinely different" carrier, not just an MVNO using your carrier's network.

After that, I think collecting a bunch of data will be necessary...

Which carrier are you using?
Can you keep a log of 10 instances when the call quality drops? Is it always right around 15 minutes, or is it a range from 10 to 20?
In the log also note whether or not the call drops.
You wrote that the situation didn't occur when the SIM card was in an iPhone SE 1. Can you put the SIM card back in that device and verify that the call-quality issue does not occur that way?
You wrote that your wife's Pixel 8a on the same carrier does not have the problem. If you swap SIM cards with your wife and make a long call (to a third party) from both devices, does the call-quality issue follow the SIM card or does it stay with the Pixel 7a?

ZoraIsHere

de0u First of all, thank you really much for the time and effort you took into your response! I appreciate it! Here are the answers:

I use Vodafone Portugal via Roaming at the moment
I did everything which was written in the GOS Usage Guide. It didn't fix the problem
When I use the simcard of my wife (same carrier) in my Pixel 7a, the issue is still the same. She doesn't have that issue which her Pixel 8a on GOS.
Still the quality doesn't drop on my iPhone SE 1. Generation with my simcard

So for me all in all it looks like a software issue. The call quality doesn't drop after exactly 15 min. Today I had a call where it was after 22 min. But it's not that it drops after 30 min or 1h. So i would say the range is between 12-22 min at the moment. The call didn't drop at the last calls I had.

You said I "should keep a log". What exactly do you meant with that? Is there a function on GOS to log calls or did you mean I should write down the exact moment the quality drops?

Thank you again for your effort!

de0u

ZoraIsHere So for me all in all it looks like a software issue.

Cellular systems are too complicated for me to draw that conclusion based on the evidence available so far.

Among other issues, if you and your wife are both running GrapheneOS, except on different hardware, and she doesn't have the problem, it's not clear to me why the conclusion would be that this must be a software issue. If flashing your device to Google's OS made the problem go away, and flashing back to GrapheneOS made the problem reappear, that would start to implicate software.

ZoraIsHere You said I "should keep a log". What exactly do you meant with that? Is there a function on GOS to log calls or did you mean I should write down the exact moment the quality drops?

By "Can you keep a log?" I was not referring to using some logging software; I was suggesting that you, personally, note down the details of what you experience. I think it might be productive to record date, time, how long the call was before trouble occurred, whether or not the call dropped, and where you were at the time.

The symptoms described so far do not clearly implicate anything, so it's not yet clear whether this will turn out to be solvable.

de0u

ZoraIsHere I did what you mentioned and noted the calls and in 16 of 20 calls, the call quality dropped after exactly 11 minutes.

This is interesting. It sounds as if you are experiencing audio-quality degradation after 11 minutes in 2G calls on a Pixel 7a running GrapheneOS, but not with the same SIM card in an iPhone; your wife, who has a Pixel 8a running GrapheneOS, does not experience this. Is that right?

Earlier, you wrote:

ZoraIsHere I use Vodafone Portugal via Roaming at the moment

Can you say more about that? Which carrier's SIM was being used while roaming onto Vodafone's network in Portugal?

ZoraIsHere

Sorry, for the late reply, but I did a couple of tests within the last weeks. I did what you mentioned and noted the calls and in 16 of 20 calls, the call quality dropped after exactly 11 minutes. I also did a couple of other tests, but it stayed with the 11 minutes:

I got a second SIM Card from another provider
I used another App for Calling (Fossify Phone)
I created a Work Profile and activated Google Services in there

As mentioned initalliy, the problem only occurs when I do calls on 2G. That is, because I work often from abroad and depending on where I am, the provider does not support 4G in Roaming there. If I have calls with 4G the issue doesn't appear.

Any more ideas what I could do (except contacting google for warrenty reasons)?

ZoraIsHere

de0u This is interesting. It sounds as if you are experiencing audio-quality degradation after 11 minutes in 2G calls on a Pixel 7a running GrapheneOS, but not with the same SIM card in an iPhone; your wife, who has a Pixel 8a running GrapheneOS, does not experience this. Is that right?

That's exactly right. Also it doesn't matter if I use a bluetooth headset, have the phone on my ear or on speaker. Also with my SIM Card on the Pixel 8a with GOS of my wife there is no issue.

de0u Can you say more about that? Which carrier's SIM was being used while roaming onto Vodafone's network in Portugal?

SIM1 (physical): Germany: Vodafone Germany -> Roaming: Vodafone Portugal
SIM2 (eSIM): Germany: Telekom -> Roaming: MEO

The Telekom SIMcard I bought for testing, if my problem appears also with another provider -> which it does.

Snibby So if at all possible, my suggestion would be to get a SIM from a provider which offers VoLTE whereever you are.

Thank's for the suggestion but it won't work for me. I work for a german company and have a lot of clients in germany I have to call. A lot of calls going on german land line numbers which means that my calls or done over 2G, even I have VoLTE in Roaming via my Telekom contract. So unfortunately that won't solve my problem.

Snibby

I had the same issue a while back. Phone calls started normally, but after a while (might as well be 11 to 20 minutes, I did not measure) would suddenly have extremely bad quality, mainly voice cut outs and such, which made it hard to impossible to understand the person on the other end.

This was with these parameters:

using stock OS Android 14
Pixel 7
Fossify phone app
most importantly, using 2G calling

I solved the issue by enabling VoLTE calling. I did not have VoLTE calling before since I had disabled many apps on the stock OS, including one (I think it was carrier services app) which is responsible for shipping the correct configuration for every carrier. After enabling this app, the OS could load the configuration for my carrier and VoLTE was available as well as Wifi calling.

Afaik, GrapheneOS also ships these configurations.

So if at all possible, my suggestion would be to get a SIM from a provider which offers VoLTE whereever you are.

de0u

ZoraIsHere Honestly I suspect if the issue is confined to 2G calls on the 7a:

It is an upstream issue,
Upstream (meaning Google) might not care.

I think the number of 2G calls is dropping rapidly, and also I suspect the number of traditional-telephony voice calls longer than 11 minutes is dropping too.

If what matters most to you is outgoing calls, I wonder if a VoIP app might work better when you are in 2G situations?

Snibby

ZoraIsHere A lot of calls going on german land line numbers which means that my calls or done over 2G, even I have VoLTE in Roaming via my Telekom contract. So unfortunately that won't solve my problem.

So calls to mobile go through VoLTE but all calls to landline numbers always use 2G or can't make use of VoLTE? What about Wifi calling?

de0u Honestly I suspect if the issue is confined to 2G calls on the 7a:
It is an upstream issue,
Upstream (meaning Google) might not care.

Yeah it might be an upstream issue or even a hardware issue on Pixel 7 series devices. If this matter is really important to you @ZoraIsHere , you could try a Pixel 8 or 9 and see if that solves this 2G calling issue. I know it's an expensive solution, but we are running out of other ideas I think...

ZoraIsHere

Within the last days, I might have found a solution. I had 3 callls while my phone was charging. The quality didn't drop. Is that also pointing to an upstream issue?

de0u Honestly I suspect if the issue is confined to 2G calls on the 7a:
It is an upstream issue,
Upstream (meaning Google) might not care.

In case it is an upstream issue: Is there a way to contact google without a google account? Not sure I want to go this way but just generally asking.

de0u If what matters most to you is outgoing calls, I wonder if a VoIP app might work better when you are in 2G situations?

Thank you for that hint. I saw that there is a german company offering VoIP (Satellite.me). I'll try that one.

Snibby So calls to mobile go through VoLTE but all calls to landline numbers always use 2G or can't make use of VoLTE? What about Wifi calling?

Yes, if I call a landline, its going over 2G (at least the landline numbers I'm calling). WiFi Calling is not supported while roaming

Both of you, thank you really much for helping me!

de0u

ZoraIsHere Within the last days, I might have found a solution. I had 3 callls while my phone was charging. The quality didn't drop. Is that also pointing to an upstream issue?

I would say that is weird, and doesn't say much about the locus of the problem. Maybe run that experiment more times and see if it holds true?

ZoraIsHere In case it is an upstream issue: Is there a way to contact google without a google account? Not sure I want to go this way but just generally asking.

I think before contacting Google it would make sense to have several people reproduce the issue.