Just got off the phone with D* and they are aware of the tuner 2 issue. Both my HR20-700s are experiencing this problem. Just last nite my wife was recording one show and watching channel 5. On a commercial she switched the channel and when she went back to channel 5, the dreaded 771 pops up. Checked and no tuner 2. The CSR I spoke with checked with the technical dept., and sometime this week they are downloading a fix for this issue over the phone line. Hopefully this will fix the problem.