I've got a problem with my Dish VIP722 reception of OTA HD sound. Silence on most channels: Fox 2.1, NBC 4.x, ABC 7.1, CBS 13.1, and religious ones in Albuqueque. My HL-T5687 sound works on some: PBS 5.x, more PBS 9.x, CW 19.1. Could some be PCM and others Dolby so that 722 is not getting one? All work directly over the air. I've never had this problem with prior HL-S5687.
BTW, I switched to the Avical starter set and after an hour to adjust myself, I like it.
Update: A reboot added the channel I was on. Same with switch check and maybe another. A subsequent reboot lost the 4.1 signal it had gained but gained 4.2 subchannel. Really RANDOM.
All seem to be Dolby Digital by the TV and not PCM. I noticed that some report PBS bad others (like me) find it works.
-Ken