said by Anonguy :Sounds like a failing Hard Drive. The 8300HD is and older modem and may have an aging HD in it. Have you had that box for a while?
Yeah, best part of a decade! (installed new in 06)
Having said that, it's been very reliable in all that time, which is one of the reasons I've resisted any temptation to change it (the others been no compelling need & the fact that it was a known quantity as regards external HDD support).
Whilst accepting the possibility of the internal HDD being a cause, it's not exhibiting any of the obvious signs of impending doom (clicking noises, recordings hanging on playback) that I have heard/seen previously when an earlier external HDD that was hooked up started to die. The reverting back a week is behavior I've not seen previously - I'm guessing that that the recordings table of contents data was corrupted & the box reverted to a backup, but that's merely supposition on my part.