Panasonic AG-W1 only plays linear audio after head cleaning?
 

I recently had distorted playback on a hi-fi EP tape (that I know is not damaged). I didn't trust the AG-W1's "auto cleaning head" feature (I read that it's just a little wheel that eventually gets dirty) so I used a head cleaner tape with some drops of MG Chemicals 407C. I waited a few hours before playing a tape again, and now it only plays linear audio on every tape, no hi-fi whatsoever.

Is this the type of situation where I may have to open the unit and use chamois swabs and rubbing alcohol on the head drum?

Hard to say what is going on. Head cleaning tapes were inferior to a proper manual clean as a technician would do. Cleaning tapes never really clean the tape path properly. Was the head cleaning tape designed for both wet and dry cleaning? Was it designed specifically for that cleaning fluid?

At best I guess the heads have somehow been made dirtier than before. At worst a hifi related head(s) has been damaged. If you can, have a skilled person open up the deck and check it out.