Android - Reduce minimum in call volume

1. Place a single layer over the speaker.*
2. Repeat Step 1 as needed.

*Works with Wii-motes too.

I was reminded by a friend that the CyanogenMod ROM I am using includes 'DSPManager' which is essentially a graphic equaliser with profiles for Headset, Phone Speaker and Bluetooth Device.

By lowering all the levels for the Phone Speaker profile I have managed to reduce the minimum in call volume (hooray!).

For people using ROMs other than CM on a rooted device, I believe a combination of DSPManager APK and modified audio library can be flashed but people appear to have had mixed results.