I have been plagued with sound fallout problems ever since getting a Sky+ HD box.I had no problem for several years with Sky + and exactly the same hifi equipment & setup. I have been running sound through an expensive optical cable to my Arcam pre/power amps. After numerous visits from bewildered sky engineers & three changes of box I bought a coaxial lead to see if that made any difference. It didn't. Sky are less than helpful.
I am now ready to pack my skybox in and take out a TiVo account.

However, one of the suggestions I have read on other forum sites is that the problem is down to the way that Sky is now encoding its programmes. If this is the case will I still encounter the same fallout of sound watching Sky tv on the TiVo box?
Any thoughts would be greatly appreciated. Thanks.

http://forums.digitalspy.co.uk/showthread.php?t=1472570

Here is a thread from last year about sound drop-outs.

The only problem I know with Sky boxes (not just HD boxes) was with Denon amps of a certain vintage.

The difference between old Sky boxes and Sky+ was that we were able to get Dolby Digital sound and that was the source of the problem with Denon amps.

Obviously 5.1 is something you want and you've likely tried it already but have you disabled the Dolby Digital sound so that the optical only outputs stereo/PL2x?
Does it happen on every single channel?

If that does change things then you may well find the same problem with Tivo as most of the HD channels , even BBC output a DD bitstream 24 hours a day regardless of whether the programme is 5.1.

The Denon was fine with 5.1 but non 5.1 sound on a DD bitstream caused breakup.
There never was a cure until you got a different amp