Just to cover your bases, did you try different batteries and card? Perhaps there's an internal clock/settings battery wearing out, too.
Jacks wear out, and the original R-09 had a weak one; maybe the HR does as well; but they can be fixed.
My original R-09 is still holding together with the silicone holding the jack in place:
http://taperssection.com/index.php?topic=164511.0I mainly use the M10 nowadays, but still use my (non-HR) R-09 occasionally when I want another source for open taping.
I've considered the R-05, too, but the pre-record buffer is only 2s compared to the 5s on the M10. I haven't used the R-05 myself, but I can say the M10 is easier to operate entirely by touch (keeping it in pocket for 007 situations) than the R-09 because the Hold switch is bigger.