There could be different causes for the source of the problem. First you should close all the background applications. There is a possibility that a background application is currently playing something and the audio driver captures the music and streams it while you call. You should also check for the drivers installation and its support software. Tweak the settings to their default values and leave them as they are.
There are no other causes other than the ones presented above, except the possibility that the device is faulty and it actually needs replacing.