Audio issue when streaming wirelessly

Hi there, I have recently setup my WD Live which accesses my video files on my PC. I have used both Media Share using Tversity and accessing my video folders directly from my PC. The WD accesses the folders in VOB format and plays it.

However within a few minutes I lose the audio while the video is still playing. I am running this from a XP Pro SP 3 PC using a D-link DIR-655 router (Pre-N) to wireless link from my pc to the WD TV Live.

Can anyone suggest a solution please. Thank you. Cheers,Isaacs George