I'm serious: try lubricating one with The Last Factory lubricant. More than one application may be necessary. It sounds like a loss of lubricant and it's causing a dry stiction--at least that's my best guess at the moment.
They still show no trace of debris after playing (and stalling) repeatedly, though not much tape went through. Similarly, nothing flaked off in the new shell.
Richard L. Hess email: richard@xxxxxxxxxxxxxxx Vignettes Media web: http://www.richardhess.com/tape/ Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX