I have read posts about this problem, but all talk about the it occurring with DD 5.1, optical audio, etc. We just have a simple HDMI cable from the ROAMIO to the TV input, using the TV speakers for sound. The Roamio worked fine (we've had 5 Tivos!), then after a few months we suddenly we had no menu sound effects... then did, then didn't, and so on. No changes - same input, channel, video & audio source... We almost returned it to Tivo as a defective unit, but thought I'd ask about it here first. Do we indeed have a defective unit? If not, what do we do to stop our sound effects from cutting out? Thanks for any advice you can offer!