IMD

I doubt of something like over-voltage protection in speaker driver LSI. By measuring of oscilloscope, I found it has a charge-pomp booster to make 2x vbat. Output voltage may down when louder volume or battery discharged. (But why only right speaker?) (Parameters of the protection were not initialized only on right-speaker driver?) I want schematics...

The problem happens when battery voltage > around 4.1V on my phone with droidian. Please check while true; do cat /sys/class/power_supply/battery/voltage_now; done I think it is not related with temp or charging state.