All I did was remove the formula to set the volume to whatever the user has their bluetooth set to and now the volume pumps out at the same volume as people talking to you...at least on my headset with my hearing.
This has only been tested on Android 4.0.3, on AOKP build 19, and only on my phone thus far. Theoretically, because it was just one line that was modified, it should work on any 4.0.3 phone/ROM as long as the VoiceDialer app was not modified by someone else. If it was you will lose those changes.
WARNING - DISCLAIMER - I am less than a script kiddie here. A blind mouse if you will. I am not responsible for any problems this may cause you, your family, your co-workers, your phone, or any other issues perceived or real. NOOBs know more about this stuff than me.
You can flash the zip file below in recovery and it will replace the VoiceDialer.apk in the /system/app directory. I highly recommend you make a backup of that file before you do this so that if you have other voice dialer or bluetooth issues you can go back to not hearing the thing.
If you do have issues, try going into settings, apps, all, VoiceDialer and clearing cache and force stopping. The app by itself without the slight adjustment here just behaves buggy to me...but your mileage may vary.
At a later time I may adjust the wait times and see what else I can find.
Check out Roman's AOKP page for a great ROM, and Zaphod's mod for the landscape in call screen....These guys are doing really great things.....
UPDATE 2012.02.04: Flashed AOKP M3, Zaphod's phone.apk, and a few other things along with this and it works on my phone. Emphasis on MY PHONE. If you update to AOKP M3 I you will have to reflash this app, but you shouldn't have any problems.
UPDATE 2012.05.10: Have been using it with AOKP B34, M5, and probably this weekend on B35. It seems to work fine with 4.0.4. I have been playing with customizing the voice and text prompts, but not updating the app yet. When I can get a settings screen and work on a couple of other things with the app I will post it here, then you can customize the text and voice strings yourselves...but no guarantees I ever get that done though...
Edited by fordpref, 10 May 2012 - 10:16 AM.