[FIX] Galaxy Nexus GSM low latency audio playback

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In my opinion one of the main flaws of the Android ICS OS the big audio playback latency - about 88 ms. This impacts negatively many applications that emulate musical instruments and the ones that do VOIP like Skype or Google Talk. For VOIP apps the audio lag also has a negative impact on acoustic echo cancellation - probably the most difficult feature to implement on an Android phone. In spite of many user protests and requests apparently Google has chosen not to do anything about it.

This is a similar thread to the one started by "Windows X":
http://forum.xda-developers.com/show....php?t=1621914
but the solution is applicable to the Google Galaxy Nexus GSM phone ( or with custom ROMs based on ICS 4.0.4 GSM (maguro))

The attached package should be used only by experienced users that can eventually restore their system to the original state. I tested it only on ICS 4.0.4 GSM phone build IMM76I (maguro). In this configuration it worked flawlessly as far as I could test it. Other successful testing reports coming for CM9 Nightly Builds, AOKP and rascream maguro ROMs.
The latency after aplying it should be about 20 ms - as reported by the "Caustic 2" app.

Change log:
Original package replaced by "lowlatsnd_inst.zip"
To restore to original state you may use "lowlatsnd_rest.zip" or other restore methods if necessary.

Status: stable
Note: applying this might reverse changes made in other mods.

consider submitting to AOSP once you're sure it's stable

Actually I think it is pretty stable, but I tested it only on my ICS 4.0.4 GSM phone build IMM76I.

Originally Posted by vonVideo

Actually I think it is pretty stable, but I tested it only on my ICS 4.0.4 GSM phone build IMM76I.

Ill be trying on AOKP later today, but as its just a modified AOSP, I dont expect any issues. Nice find!

Originally Posted by vonVideo

In my opinion one of the main flaws of the Android ICS OS the big audio playback latency - about 88 ms. This impacts negatively many applications that emulate musical instruments and the ones that do VOIP like Skype or Google Talk. For VOIP apps the audio lag also has a negative impact on acoustic echo cancellation - probably the most difficult feature to implement on an Android phone. In spite of many user protests and requests apparently Google has chosen not to do anything about it.

This is a similar thread to the one started by "Windows X":
http://forum.xda-developers.com/show....php?t=1621914
but the solution is applicable to the Google Galaxy Nexus GSM phone.

The attached package is in an experimental stage and should be used only by experienced programmers that can eventually restore their system to the original state. I tested it only on ICS 4.0.4 GSM phone build IMM76I.
The latency after aplying it should be about 20 ms - as reported by the "Caustic 2" app.

So that's why I have an echo on almost all of my phone calls and voip apps?
Is this a flashable zip or something you have to include before compiling?

It is a flashable zip.
The big audio playback latency is one of the reasons for echo cancellation poor performance.

I'm guessing it's possible to manually paste these files into the phone via some form of root explorer, right?

Since I'm new to the GN (had a Desire before), is it possible for you to create a flashable version of the stock files which will get replaced, as a precaution, please? Backing up and restoring takes quite a while (some minutes vs. a few seconds compared to a patch )

Edit: maybe I haven't noticed it, but I'm on 4.0.4 update 2 (forgot the exact build number - as I said, I'm new to the GN ) so... where exactly (or rather, how) can I spot the differences before and after applying the patches?

Actually I have included in the zip the original libraries too with the extension ".orig" for ICS 4.0.4
They may work on 4.0.2 too, but I did not test them. You can copy your original libraries for example in /data/local/tmp/ and restore them later if you need by mounting system rw...

Tested this on the Modaco ROM ..
Seems to break system sounds. Music doesnt play anymore.
Phone calls still work though...
Caustic 2 does say 20ms latency..
going back to stock for now but sure deserves attention..

Unfortunately I don't know the Modaco ROM. On ICS 4.0.4 it works flawlessly with any sound source I tested so far.