OK- I redid the audio/video wizard and selected HDMI 2, 1080p and 60 hz over a HDMI cable to my 46" Sony Bravia.
On my setup, dvd's play without a hitch. No lag, no tearing, no frame drops. Everything plays as smooth as I could hope- everything, that is, except the audio. Although I managed to break the laws of physics by losing my remote in a closed system... the mass of my remote is no longer within my closed system bubble- at least not that I can find.
I check the bios settings and disable acpi and I ran alsamixer from a putty terminal to confirm that IEC958, IEC958 D and IEC958 1 were not muted. What I find odd is that while the other channels (mic, CD, line, center, etc) have volume slider bars, these do not exist for the IEC958s. The only option for the IEC958s are infinity and "MM". B4rney, do you have the same?
And, for what it's worth, here is a screenshot from the webadmin:http://imgur.com/DRtrb
I tried unchecking the AC3/DTS passthrough and using vdpau as the hardware acceleration- after making these changes, rebooting the revo and doing a complete reload/regen of the entire system, I saw no changes. Media played as before (didn't test mythtv).
As a side note- from a completely off state, to a functional UI (menu completely loaded) over a 100bit network, it took 2 min and 38.4 seconds. And, from the time I pressed "restart" from a different orbiter to again to the same functional UI took 2 min and 51.3 seconds. The only non-standard items I have on the system is Hulu and a gyration remote and nothing failed to start on either restart. Well, turning off ACPI caused the system to 'halt' on shutdown, it did not shut itself off. After turning it back on and timing the shut down time (pressing "Power OFF m/d" from a separate orbiter) yielded a shutdown time (time ended when the power light on the revo shut off) of 17.1 seconds.
edit: now with url tags rather than img tags for link...