I, too have dishnetwork DVRs. Have 721s and 508. No problem with what you have described. Probably you called dish. IF you have the $5/mo coverage they will swap. If you don't, you might consider getting it. I'm glad I have it. Just got a replacement within 2 days for a 721 with HD failure.
...and I like the 721. Actually I have two 721 hooked into my 990. Both use RF remote. THe one in the basement connected to 990's Video 3. The living room 721 to Video 2. I can send either to records outs. Plus there are some other mixdowns that I do.

And it's nice to be able to record something while watching something else...or two simultaneously.
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Living Room:
5.1 Surround and 4channel inline room
990/7700/6-KEF-107s/LFM1 x 2/ SMS Awaiting Trinnov
Millenium dts decoder;Digital Director
Players: Tascam CD01U/SonyCX455 x 3/DV955/BDP83
Old Sony 60" SXRD TV
Zone 2 (also liv-Room: listening to music while Mrs watches TV): Crown SL2 preamp/D40 Amp/Stax Headphones



My "Man-cave":
4 channel-only inline room. No TV (thank heaven)!!!
990/755/4-KEF 107s
Tascam CD01U/dts decoder/digital director
Alesis 16x4x2 mixer
Recorders Alesis HD24/ML9600/Crown CX844s/SonyDAT/Tascam DA38
Ham Radio Shack (KB1STH) ICOM/Yaesu/Drakes x 3