DDJ 800 Controller momentarily disconnecting from Rekordbox software when table or laptop is bumped.

I have a DDJ 800 controller it is in very good condition and has had minimal use so am puzzled as to why there might possibly be a hardware issue. I plug my DDJ 800 into my computer and am playing, whever the table, decks or laptop are bumped a certain way, the decks disconnect. The message flashes up on my laptop saying DDJ800 disconnected (screens on jog wheels go the blank rekordbox screen). If nothing is bumped there are no issues however when it is bumped it reconnects almost instantly but as usual it takes a little time to become functional again and get the music playing again. I am thinking it is a hardware issue because when I went to sell the decks, the buyer bought them took them away and played at a professional gig he first used the factory USB A - USB B pioneer provided cable then the decks cut out when they were bumped so he changed to a different USB cable and the same issue kept happening when the decks or table were bumped. The usb plug in the decks has never been bumped or anything like that, but upon reading around it looks like it might be a hardware issue like a faulty connection at the solder or something. How can i go about diagnosing and then fixing.