If you are up for making your own cables, I'd suggest the switchcraft right-angle RCA connectors. that's what I use, and it fits perfectly, nice and tight, definitely no room for it to be jostled at all.
actually, I got lucky in that respect, because a few years ago, I decided to make my own digi-coax cables, with right-angle connectors on both sides. I had used the switchcraft connectors, and now I'm glad that I did.