I am having some issues with audio dropping, believe I may have some helpful information, and am wondering if any progress has been made. In summary, for me, it appears to be hdmi related.. full details below:
I have a Pace Aspen TDC776D connected to Shaw Cable. For all purposes except audio, it's working great. HD and SD and PVR behave as expected. I'm told Shaw uses MPEG2 and has no MPEG4 at this time, however I cannot personally verify the accuracy of this.
I've recently re-run cable to ensure high quality signal and do my best to rule signaling problems as the source of the audio drops. The 776D reports signal of around 0 for IB1 and 2 for IB2. Signal levels elsewhere in the house range from 0 to 2. SNR is usually good, at 35-36 or so, although once in a while fluctuates to "fair". All unused cable outlets are terminated. My home has a PCT multimedia drop amp, standard Shaw equipment, with +7db gain on all ports and active return (i.e. also boosts the signal going out of the house). All splitters are high quality Antronix splitters 5-1000MHz and 120dbi noise protection. (i.e. the stuff is all high quality).
The Pace box is connected directly to the TV (there's no amp / receiver). The TV is a Sharp Aquos LC-37D40U. Connection is HDMI. Pace is set to Auto for audio, and TV is set to take audio from digital input (i.e. the HDMI). Also, for testing, I have a rca cable analog audio output from the Pace box to the TV, allowing me to change which audio feed to use on the TV (i.e. change between digital and analog input).
When audio drops, it goes away for about 1 second, and then returns. It will do that approximately 2-4 times per hour. Audio drops have only been seen on HD channels. Also, they're in live, recorded, and 'delayed' watching (i.e. watching 15 seconds behind live).
When it occurs, I test by rewinding the DVR to see if the audio drop is still there. For almost all of my testing, the audio drop does not appear in re-play of the same scene. Finally, I've tested by using the analog/rca audio instead of audio over hdmi, and found no audio drops when using analog/rca inputs and not hdmi.
I don't know if this is helpful for anyone or not, but thought I'd post it. Since I'm only using tv speakers, the digital capabilities of the digital audio are less important to me, although the ability to use hdmi universally would be nice.
I'm welcome to any questions or other info people may want.