What is the colored label/part of the RCA jack called?

I’ve have had that happen in the past, but only on lightly made equipment, often a printed circuit board inside, with several pairs of inputs or a board with outputs, the board flexes, things move/loosen/break.

I pay more attention to the quality/solidness of the jacks within that manufacturer’s line, you can check a different model at a store, see if they are strong, before buying something from that manufacturer.

Also, buy returns accepted, out of the box, push/pull/case thickness ... keep or return.

I just pushed like a maniac on my McIntosh preamp from the 60's, probably could take a hammer to them. New 'Chinese' amp, extremely strong, beautiful construction, ...

kgbspy, agreed, if the insulators are popping out on my RCA jacks, I would replace the complete jack assemblies if possible.

nobody sells those colored pieces of plastic... i guess you can buy complete replacement jack and disassemble for needed pieces   

Heat shrink, right. You want that anyway. Comes in real handy.

Get some red and white heat shrink, slip a piece over the IC and use a hair dryer on "high" to shrink it on (red-on-right, white-on-left). Also, Home Depot sells colored electrician's tape that works well.