Sound issues in FS?

I am finding that when minimizing FS then returning it to focus later, that I have lost the sound from FS. I also appear to have lost sound for other apps as well. This also sometimes occurs when switching between views in FS. It's rather random in nature (doesn't always occur, but is a "pain" when it does :) ).My sound (imbedded chip) is a Avance AC'97 chip, imbedded into an ABit BD-7II motherboard. Any advice as to how to get rid of this problem?If I do end up going to a PCI sound card, any suggestions? I would need to have something that I could use with VATSIM, etc. (mic is in duplex mode).Thanks,Bruce.