Vtech BM4000/VM341 Safe and sound linking problems

My units were working great until recently, where the camera got knocked onto the floor and may have been damaged slightly. The sound of lullabies when played from camera is getting stuck on notes sometimes unless the power cord is held in certain spots.

The biggest problem is linking between parent and baby unit barely functions now. Tried unlinking and re-linking, took me almost an hour to get a re-link to work! Just wondering what the problem could be and if its repairable ? I have carefully opened the camera (baby) unit and nothing is damaged as far as I can see (no soldering either). Thinking it is a power pin cord issue..?

Any advice would be great!