[AOSP] Speakers clipping and distortion

[rinigus]

This is to follow sonyxperiadev/bug_tracker#411

In short, speakers clip on high volume and it may damage device. See the linked issue for description.

Workaround for now:

• after flashing, but before booting into Sailfish, UNPLUG USB cable. This will prevent charging sound on the first boot
• after boot and passing through installation, change volumes to a lower ones.
• drop all system sounds for now

[Gouster4]

This issue should be fixed recently on sodp 4.14 kernel... Not sure if 100%, but its better than before.

Im also not sure if its kernel or android issue. So maybe fix is not on 4.14 kernel but on android 10 sodp commits.
I hope for kernel.

[MartinX3]

Yes
Sodp switches to the CAF audio hal and the next OEMv9 will contain updates
Also there are open PRs for akari/Apollo/akatsuki

With will also work together with the new VoLTE feature which should be completed after the next OEMv9

Aaand to help with the distortion please clean your upper speaker membrane

[rinigus]

@Gouster4 and @MartinX3 - thanks for heads up! We are still on AOSP9 though and while @MartinX3 has mentioned TWRP/4.14 hybrid, it will have to be tested whether I can achieve it for SFOS. Not sure whether CAF switch would also require some re-basing which is not trivial for us.

I am pretty sure that the speaker membrane was clean when I heard it first time, as my device was new. But cleaning regularly is a good idea anyway.

I may have to rebase to AOSP10 eventually, as it sounds like it is improving there, and make the port based on that. But would prefer to wait till some other AOSP10 ports are done first and focus on other projects meanwhile.

[rinigus]

Suggested in https://forum.xda-developers.com/t/gnu-linux-4-0-1-48-sailfish-os-for-xperia-tama-devices.4008681/post-84965183

Would it be an idea to limit the maximum volume of pulseaudio sink output to a lower level to prevent clipping?

I currently run "pactl set-sink-volume 1 75%" after every boot so that even if I set 100% volume in user space the speakers do not clip.

[ApostolosB]

Is this considered fixed??? It kind of seems better than what it was on aosp 9 but some sounds -ie the new email notification- still sound like they clip.

[rinigus]

TBH, I haven't checked by pushing it. It may have been closed upstream as the cleanup of the issues. So, I suggest to keep it open as a warning. Unless someone confirms that this is resolved

[ApostolosB]

I don't know what is considered correct though. I tested this mainly by playing various albums from the media player. Some that are recorded "loud" and are bass heavy seem to make the speakers distort and others that are less "loud" seem to behave fine even at 100% (full volume bar). If it was up to me i would probably set the sink volume a bit lower to handle that distortion (~70% maybe).
Also. The notifications (email, phone ringing) seem also to be on the loud side. Kind of like feel distorted with high ringtone volume.
I'll probably play a bit more in the next few days and report anything i find.

[teleshoes]

was gonna open an issue, but it looks like this is the same issue.
sounds are ludicrously loud during first boot. keyboard feedback sound while typing wifi password literally made me drop the phone. sound levels became normal after about 60s, on their own, between one keystroke and the next.

it does seem fixed in subsequent boots, so maybe something sets volume with pactl during the boot cycle now?