I have two questions concerning the operation of the LM49350.
1. I have the Left microphone configured for mono, connected to Left ADC and then to Port 2. This configuration works fine. The HPL/HPR is connected to the Left DAC and then to Port 1. I connected a load resistor across the microphone input and recorded silence at -70dB. I am using a file that has all zero's to simulate silence and playing ti out HPL/HPR. I see the noise floor increase from -70dB to -40dB on the microphone. What would cause the noise to increase on the microphone when playing sound out of the HPL/HPR.
2. I am using a microphone that has a 3 pole connector,TRS(tip, ring, sleeve). The T and R are connected together and the sleeve is ground. I designed my codec circuitry so that I can use one connector for either a microphone or a headset. I employ analog switches to connect to the codec. When using this particular microphone the R is connected to HPR. The HPR is disabled. When the HPR is disabled is it open or connected to a power rail? Ground?
