Hmm-
Regarding my current 8-beep problem, it seems to be a warning that concerns the vacuum motor. Some lists of 'beep translations' are incomplete and leave out the 7 and 8 beep error causes- mainly because these were disabled in versions later than mine, apparently.
The troubleshooting pages at iRobot has this to say about it:

Quote:
What do I do if my Roomba stops, says 'uh-oh', and beeps 8 times?

Make sure the Dust Bin is properly seated in the Roomba. You may want to try wiping off the metal contacts on the bin with a clean, dry cloth. You also should try popping the grate off the back of your Roomba and ensuring the vacuum is spinning freely. If this does not resolve the problem, please call Customer Support at 877-855-8593.

I haven't found any joy with those tips.
I've found that the problem is most prevalent when the battery is less than fully charged and the filter has seen some hours of use.
*sigh* I guess I'll be calling CS.