JVC M90 Cassette Won't Eject (Help)

[aiwapanasonic]

That's an extremely thorough M90 restoration, great find! Here's the translation if anyone needs it link

I know, they disassembled every single switch and pot! The volume pot had the broken sliders so good on them! But they didn’t recap, that is interesting. Of the eight or so machines serviced recently by my restorer, only one needed some recapping but not the others.
My favourite photo is the four m90’s stacked together, it’s beautiful!

 

[JC Slater]

*** UPDATE #2 ***

Good news, I don't think I broke anything! All 3 belts were replaced, the deck is now fully functional and plays at a consistent speed without any fluttering. Only thing now is the tape speed, which is pretty much chopped and screwed. Tapes play at a very noticeable 10 BPMs slower than it should be, any suggestions? I believe there's a speed adjustment on the motor, could it possibly be under this white plastic hole? If so, what kind of tool should I use and which way should I turn it. Thanks...

 

[Superduper]

Use a tiny jewelers flat blade screwdriver, or even better, a plastic electronics one if you can find, and don't force anything. If it doesn't feel like you are turning a potentiometer, you might not be, and you might actually be prying on a diode or something if the blade isn't aligned right.