Linn LP12/Lingo start-up/speed problems

I have a Linn LP12/Lingo 2 that has started to display issues on start-up; firstly it takes a long time to get up to speed and motor/sub-chassis/arm-board shake during start-up and secondly the motor/Lingo will just die during play and the record will grind to a halt. I was hoping it might be the motor as I could change this my self but Linn thinks it is a problem with the Lingo which requires a visit to the dealer; has anyone encountered a similar issue?

I bought the Linn in 1991 with a Valhalla power supply but upgraded to the Lingo a few years latter. The motor is the older version with a cap/spring/ball bearing on the bottom of the motor shaft. I have read that these items can be dispensed with the Lingo power supply; any comments anyone?

I had those symptoms when my Valhalla board died. You could look into the DC motor kits out there for a few hundred bucks for the LP12. They get good feedback but I haven’t heard one.
I'd be very surprised if the problem is mechanical, rather than electronic. I had a Thorens TD-125 Mk.2 whose electronics created the same "motorboating".
I  agree to start with removing cap, spring and ball before doing anything. It will do exactly what you discribe. It's easy to do, just do it slow because spring can through ball and you will be on your hands and knees looking for it like I did. Soon as I did it problem solved. Mine did it with Pink Triangle pink link power supply not lingo.