OK, I know that everyone is going to say "replace your hard drive", but here goes. I've got an original Series 3, probably five years old. In the last few weeks, it has been stuttering, and (worse) truncating recordings that appear to have completed. So you'll say "bad disk", but here's the rub: I ran the SMART tests on both the internal and the external drive, and both came up 100% clean. The problems seem to occur when two recordings are happening, or when I'm playing while a new recording is happening. Short of the "Hail Mary" replacement of the drive anyway, are there any ideas?