Specifications for CableCARD products require support for AC3 audio streams. We have found that there are numerous cable companies who either don't generate an AC3 track or the track they do generate contains blank audio. We have been working to notify the noncompliant providers as we find out who they are. We continue to advise them of this shortcoming if they are not responding, but there is only so much pressure we can apply. In the meantime, we will be adding support for MPEG2 audio in our next major software release. Keep in mind that the Series3 DVR will still default to an AC3 track, if detected, even if that track only carries a blank audio stream. If your cable company continues to provide you service in this manner, it may be in your best interest to contact them directly. We are more than happy to point out that the specs call for a valid AC3 stream. We had hoped our communications to the providers would've proved fruitful before now, hence the delay in posting this information. However, with everyone pointing their fingers in our direction, it's time we cleared things up. I hope this helps.