What next? Perhaps these tapes have SSS, as another post suggests. I have a couple of 3M-Scotch blank tapes, a Philips pre-recorded demo tape, and a box of BASF blanks. The first two types play unreliably with the pinch rollers stopping erratically. I can often hear a faint but ominous squeal. The BASF’s seem to run OK. If the tapes are afflicted, they probably shouldn’t be used, so that the tape path won’t load up and need to be cleaned.