Marantz SA-14 acting up

This is an older player and has been a good one but now has developed problems. When you try and load a disc, the tray closes very slowly and then opens right back up. Any ideas please?
I had a similar problem on a Consonance CDP and it turned out to be a micro switch. It didn't happen all the time but enough to annoy me. Then it happened more frequently and luckily it was under warranty.

With labor going at around $65/hr just to look at it and hoping it's that particular problem, this could be expensive if the part isn't readily available.

Good luck,
It sounds like something is jammed the transport. I would take the cover off and look inside.
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I lubricated the slide last night which didn't seem to do anything at the time but, by morning, the tray was going back in as normal.

It's taking longer to a read a disc but still plays and, BTW, what a difference between it and the Rotel I was using as a back up. The Marantz sounds awesome in comparison!

Thanks to all that took time to comment, I appreciate it!