Hello, A while ago I received a WM-D3 with replaced center gear for a decent price. However what the previous owner did not tell me that it has a horrible whining sound and my local audio repair business could not fix it. I opened it up and found out the new center gear makes this noise. The noise can also be heard in the audio during play and recording One of 3 "ribs" also hits the play mechanism which makes me suspect the gear is not properly aligned. Before I disassemble further, what do you guys think what the problem can be? I can take out the center gear but then what would be the next step? I should also note the Walkman came without any oil or grease on the gears so I put a drop of sewing machine oil in but that ofcourse did not solve the problem If allowed I can send a link to a video containing the whining sound Link to the video: https://youtube.com/shorts/vc8CSTaoeoA
Because the sound is so constant, I think the problem lies more with a squealing motor bearing or something similar. The front bearing of the motor is easy to lubricate. I do hear the gear grinding a bit, so aligning it better with the metal disc wouldn't hurt. Especially if the cams on the gear are hitting the play-lift mechanism.
