Richard I don't get it. If you exchange the motherboard and it doesn't change,I would wonder why the problem started and now couldn't get fixed with a different same motherboard. So upgrading the motherboard sounds different to our problems. Eg. It wasn't a problem till now, and if it's the motherboard a same new one should work.
Anyways I can check with an internal sound card I have lying around. Should verify its the motherboard. Will also shutdown computers power fully for 30 seconds and try it. As USB issues can occur and remain without a hard reset too.
Last edited by doinky; 2012-11-20 at 10:19.