04 Symbol, Problems with bed mechanism.

Hi,
Had trouble this morning getting the bed back, one side had jammed, it appears one of the two ball races in the left hand telescopic mechanism had broken.
It was the upper, smaller ballrace, I tried fitting the ball bearings back into the slots but to no avail.
I eventually took the faulty ballrace out completely & it now works, but it’s metal against metal, not an ideal situation.
Anyone else out there had this problem?£