recording problems

recording problem
I have one Genie, one mini. We watching TV on two sets, different channels. In the past we could watch two channels and record three shows without interference. Then it became only two that could record, now it isn't even one.
I have reset and unplugged the receiver numerous times with no help.
It's now common that with only one show set to record for the day, when it was time for the one show to record, one of us will be kicked off the show being watching so the recording can start. Once the recording starts we can pushed the previous button to go back to what was being watched, delayed time lost of course, and the recording continued with no problem.
What can cause this and how can it be fixed??