I had this issue a few years back and I supported the cable at the input to keep it from working loose. I used a Velcro strap to suspend it hammock style from above.
Loose fitting power cord
The power cord (Morrow) to my amp is loose fitting. It keeps falling out with the slightest movement.
Two questions.
Will that affect the ultimate SQ?
Is there any way to fix the problem short of getting a new cord?