rockola 1426 help needed

Hi Folks, my Rockola 1426 is starting to play up a
bit. Some records are starting to repeat themselves
before moving on to the next record. It usually takes
about 3 rejects to get it to move on to the next
selection. It might be something simple, something
sticking or possibly a switch needs adjusting. I have
the manual, but this symptom is not covered in there.
Before I make a start, I thought it best to get advice
from the group first so I can at least look in the
right area and hopefully not make matters worse.

Thanks

Gary