I dont really see how you can state that it records OK unless you are testing out what you have recorded in another machine, as if the tape is running out of line on playback it "will" affect recording as well, as the mechanism doesnt distinguish between record and playback as far as tape alignment is concerned. However "if" you can see inside the tape compartment have a check at the pinch roller that presses the tape onto the capstan drive, as a defective rubber roller can be one of the causes of this. PS:- Regarding suspicion of defect on playback only, this could only really be verified by playing back a tape of some previous event which was positively known to have been OK at the time.