My aim is to connect Mobile phone's Mic to Laptop headset out for injecting audio into mobile phone calls. So that Mobile phone calls should get answered automatically and system should play the recorded audio. This is not possible by programming Android or iOS. Hence i am looking for hardware approach. Searching online i got two different circuit diagrams. Not having much electronics exp, i am unable to decide which one would work. Need help to achieve this
Circuit 2 :
Note : I have tried circuit 2 and it worked well on iPhone but not on Android (Samsung). On Android audio was very garbled. Not sure whats the difference ?