[dj_fivos_sak]

Hello. I finally found the solution, and the fault was indeed inside the loading ring assembly. Here's what I did to fix the problem:
1. Remove the front panel (1 screw and 3 tabs/clips), and remove front loading mechanism and unplug it.
2. Unplug all the connectors connecting the mechanism to the Audio/Servo/Mechacon PCB. They are marked so be sure not to mix them up when reconnecting.
3. Remove the head drum grounding electrode, the RF shield over the video head connector PCB (also unplug the connector for the video heads), the chassis grounding lug with its three grounding wires, and the back-tension lever (don't touch the adjustment screw!). Then, remove the 5 screws securing the chassis/mechanism onto the cabinet.
4. Turn the chassis over and unplug the connector of the head drum motor.

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