Yes, I had a similar experience last night - all 5 recordings, after the daily timer had finished, failed to record. I didn't spot the first one until later - I deleted that timer. When the subsequent 4 timers failed, I pressed record on live tv to start the recording in each case. It's strange because although the box wakes up to start the recording, it just simply doesn't start recording at all. However, it seems to be behaving itself properly again this morning without deleting/resetting any timers (except the repeating one).
The simplest test case (after I spent ages playing with overlapping recordings, etc) is just to set a repeating timer, and after the first recording for that timer, the box will refuse to record anything else. But, if you then delete the time type timer completely, it springs back to life most of the time. For instance, when a programme is still on and not recording due to this bug, deleting the type timer then causes the failed recording to suddenly start up. I guess there is probably some code in the repeat timers that causes it to ignore all event timers until the next repeat timer (or maybe just any manually set timer).