I was out running the other day listening to music on my Huawei Glory. The call came in, played my ringtone, and paused my music player (poweramp). I was not able to hear the person calling me through the earbuds after I picked up the call, nor could the caller hear me, even after I unplugged the buds. I had to call back without the buds plugged in.
I haven't seen a setting that would change this action. It doesn't make any sense to me that I can hear the ringtone through the earbuds, but I cannot take the call while they are plugged in.
the phone is running android ver 4.0.4, and I am using the stock phone app.
The only setting I have enabled is voice privacy - although I don't know what that does - it was enabled by default and I have not changed it.

Any ideas?