A strange nose when I answer a phone call

Zoanoid

Why there is a strange noise for callers to me when I answer the call (like TRRRRRR). Sounds like some kind of interference in the network. A short noise when I answer the call. One my pal said it's been a long time, not the first year. I called myself from other phone numbers (devices) and it really is. Maybe this is a feature of only my device? I hope I'm not being bugged.
BTW, I don't have any subscriptions from the provider for melodies that play while someone is waiting for me to pick up.
What about your phone? Is there any noise?

Johnnyloans

Zoanoid

Has this noise always happened with your phone since you owned it?

Always on stockOS and always on Grapheneos? (Never tested stockOS oe don't remember possibly?)

Did you buy the pixel 6a brand new?

Sounds like this is only with calls to your phone number and not whatsapp, signal, etc.

Does this happen over wifi calling and calls over or cell connection?

Try setting sim network to 4G only. Turn off 2G usage. Does it happen with only low signal strength (low bars).

Go to your phone call app' info page > storage > clear cache.

Go to apps > see all apps > top right 3 dots > show system apps > search "messaging" > phone and messaging storage > storage > clear cache

Let us know how it goes :)

Johnnyloans

Zoanoid

Under sim options > carrier overrides

What is the "default" for every option?

Did you manually override any of these? If so which ones

Tandara

What provider are you using? Phone model? Other details? It's hard to help based just on this info :)

Zoanoid

Tandara

Pixel 6a - as indicated above :)
What other details do you mean? I had no such issues with my previous devices on the same provider.

Tandara

Zoanoid Sorry, I don't see the model written in your post, only the reply.

Today, governments just ask the phone company to record or send the phone conversations directly to the Police Department (if police was spying) without any need for interception, so we can scratch it.

The very likely cause is pure interference and artifacts. I myself experienced it during travel in the crowded areas. Unless you compared phones/sims on the exact same frequency, connected to the exact same operator, and exact same cell-tower, then there is no way to reliably tell.

Zoanoid

Johnnyloans

I'm not sure, my friend said this has been happening for a long time (maybe it was always like this).
GOS was installed on completely new smartphone. Never changed it.
Looks like this is direct phone calls' problem. The signal strength is fine usually.
About "phone and messaging storage" - there is something like "messages from the provider" (in my local language) - the cache is already empty.
Under the default profile is just "SIM settings" app from the provider. It's all about additional services. I didn't change anything there.