Bad Motor? Or Electronics?

The 3900’s have been good to me ever since I bought them. Thought a few years ago I noticed that the platters were developing a bit of a vibration. This vibration got stronger with time. :confused:

This lead to an issue where the play button sometimes would not register when it was pressed. The cue button seems ok but the play button is definitely not.

Then as of the last week I am seeing major issues with the platters. The vibration is still a major problem but now I am seeing TERRIBLE torque that is affecting BOTH turntables. :weary:

It is so bad I am unable to properly scratch and/or release a song to be on time/beat. The platter just bogs down big time and is not usable in a club setting.

Unable to buy new modern technology at this moment I am trying to do the research and figure out if anybody else here has been through this road before and might be able to provide some advice as I am really interested in repairing them. I have been told that it could be the motors needing replacement… And from what I have seen it truly does feel that way with my decks.

Hoping that maybe somebody here can testify on my case and add any feedback. Thank you in advance! ~BIS

*I Absolutely love the design and form-factor of my 3900’s which I have owned since 2012. * For me, a 9" platter is the absolute best compromise between the smaller more popular controllers (7" and 5") and the full size (12") platters. Favorite deck in all my 20+ years of DJing!

ive been DJing with my 3900’s for ever so far (knock on wood) no platter trouble but both play buttons gave out… so i contacted denon & ordered the buttons and had a local repair shop replace the buttons

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It looks like the bearings under Your motor has worn out. My friend had the similar issue with his 3500. As far as I know it is very hard to get to the bearings. Replacing the complete motor assembly would be easier. But maybe we have a handy service man here who has enough patience and time to do it. Where do You look for service?

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Was it just the plastic cover or the actual button switch that you had replaced?

that switch sir.

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I am in agreement with you, and from what I understand the motor replacement would be the popular repair. I think I may have found the motor here (if anybody can confirm this, let me know):

https://www.instrumentalparts.com/motor-unit-for-media-player-controller-fg3900/

I am in Delaware. Can easily travel From Baltimore to Philadelphia/Jersey if there is somebody that knows their way around this unit. I would even attempt it myself, but not without some kind of schematic or other info to help me avoid pitfalls (like unintentionally pulling on fragile ribbon cables and stuff like that).

Would much rather pay somebody with experience…