Hippie!!! Finally a fix for no sound issue is out!!!
From wiki.xda-developers.com
Sometimes a Blue Angel device malfunctions and causes the uni-directional sound problem. You will not be able to hear the second party, while he or she can normally hear your voice.
A patch has been issued by i-Mate for this problem. All you have to do is copy the CAB file to your device and run it. Then perform a soft-reset.
Apparently, this patch replaces the AudioGW.dll file. So far, the problem has disappea...