3. Does KA3 support in-line remote control in the headphone or phone calls answering with headphones?

1.The KA3 does not have any buttons. And it does not support in-line remote control in the headphone or phone calls answering with headphones. 
2. When an incoming call comes in, the sound is still transmitted through the phone's speaker and microphone. You can pick up the phone and make a normal call.Whether unplugging the KA3 will not affect it.