Air conditioning cool/warm lever migrates to middle

I don't see a place where I could mount it. It looks like it needs a solid surface to mount and compress the cable. I'm going to measure the cable with a micrometer and hunt for a small hose clamp that might I can tighten around the cable. I am concerned that it might lead to premature wear on the cable, though. The only alternative I see is to open the box and see if anything is loose inside that might be causing the problem.