sonusman
Banned
Have you tried switching the order of the two machines? Sounds like the Master machine is having some playback/clock issues based around the tape transport. If that was to happen, the Slave machine would suffer too! Try switching the two machines and see if it still does it. If only the second machine is freaking out, you know it is that machines transport, and you should have that looked at by a Tascam certified repair shop. If both of them are still doing that, well, have BOTH machines checked out. 
Ed

Ed