Portastudio 424 Noise and Motor Whine

[NobleStumble]

I recently picked up a Portastudio 424 and have discovered a problem with tape playback and recording. At random points during playback the unit itself will begin to whine very loudly from the cassette deck. it sounds almost like a squeal from a bad belt.

Whenever this noise happens, there is also white noise on the outputs which drowns out most of the playback. Could it be as simple as a bad belt? How would that create noise on the audio signal?

Any help would be greatly appreciated, thanks!

 

[NobleStumble]

Well, after a little surgery it looks like I'm just dumb and the most likely culprit is simply that both of the cassettes I used to test the unit are worn out and the tape is dry / needs new lubricant. Will test with a new cassette and if you don't hear otherwise, assume that was the problem.