External USB C Microphone Issue [Too Loud/Sensitive]

mrhappy

Hi,
I have a Pixel 5a running GrapheneOS on Android 13.
I recently bought an external microphone to use with the phone. It connects via USB-C, a Boya BY-M3. It works with the phone but the input volume is far too high.

Steps I have taken to resolve:

Restarted phone (did not change anything)
Tested the microphone on my laptop (normal mic volume on laptop)
Tried several different audio recording and camera/video apps, including ones where you can adjust recording volume (no change)

As it didn't change no matter which app I used, I'm beginning to suspect it's either an issue with my phone (unlikely as it's only a few months old, brand new) or something with GrapheneOS. I've tried to find somewhere to adjust the microphone input volume but I can't find one.

Any tips or suggestions on how to resolve?

MetropleX

mrhappy surprisingly you have the opposite problem to what a lot of reviewers of the mic have had in that they found the input low. So we can definitively say if this is an AOSP or GrapheneOS issue can you test with the stock pixel OS either on yours or someone elses device to see if the issue persists?

Comparing laptop to phone is apples to oranges.

mrhappy

MetropleX Thanks for the reply, sorry for the delay. Took me a while to find a stock OS comparable phone...

I have now tested it on a stock Pixel 5 OS and the microphone volume was fine. I then tested it on another Pixel 6 with stock OS with the same result.

mrhappy

Bumping this. Can anyone help?

tmp

You need to use a mic with adjustable dB gain e.g. a hardware switch to set gain -10 dB.

stkr

@mrhappy This reply probably comes too late, but did you check, whether the loudness is just subjective and comes from dynamic compression, or the audio signal is actually clipping?
Background: I have recently tested a USB-C DAC, which is much too quiet. While i don't want too root my phone to edit mixer-paths.xml, your issues could indicate, that there might be another way to adjust microphone gain, if not solely hardware related.
Officially Android does not support gain adjustments to prevent surveillance with sensitive peripherals. However this design decision is questionable in my opinion, when leading to _15dB difference compared to the built-in microphone...