I have two questions for you in regards to using the TPA2016 module. First question is are you taking the audio input to the module directly from the volume pot wiper? That was my take on an earlier post you made. I have two modules and both behave the same. One module I connected as just a stock amplifier, with no connections to the I2C bus, and the audio output is extremely low. In order to hear a 50uV 1KHz signal I have to turn the volume control to maximum. The second module I have configured with the I2C connections to the Arduino Nano and have the Vcc line for the I2C connected to the 3.3V port. The Vdd line is connected to 5V. I have the same results - extremely low audio. I'm using the left channel for input and output. My speaker is not grounded in either case.
The second question is more of a request. Would you post your modified Adafruit library files in the File section here on Groups IO? I thought I had your library modifications figured out but now I'm not completely certain. Before I start chasing my tail in the wrong direction I'd like to know that at least the files I've modified and am using are not part of the problem.
Thanks for your work, I certainly appreciate it.
--73-- Mike -- W0MNE