Lousy IEC Connections

Yes, this is an issue, and there are easy fixes for. My greatest issue with pc's is having iec into equipment being at all manner of placement. Grounds may be top, bottom, right or left, often have to twist stiff pc which pulls equipment off specialized footers. As a result, I now only use more pliable pcs.

The Furutech FI-15 Plus IEC connectors actually have a very tight fit when inserted into equipment.  This is both with the plug casing itself (which the fit into the IEC socket is very tight and snug) as well as the strength of the internal contact clamp mechanism.  The more expensive Furutech connectors are still pretty okay, but not quite as tight fitting.

The Neotech IEC connectors are tight fitting as well.

Which reminds me, what a walrus has in common with Tupperware: they both like a tight seal. 

A classic.
These are all good suggestions - cable risers, shrink wrap, friction tape, teflon tape, installing aftermarket connectors, etc. but....these are all patches.  The root cause is not being addressed; and that is ultimately up to the manufacturers.  IMO, for the money that we spend on this stuff we should not be accepting of applying patches.  I doubt that any of us would be accepting of having a new toillet installed and being told as the plumber walked out the door to make sure we jiggled the handle.

As millercarbon suggests, a couple wraps with teflon tape or in my case, a couple wraps of electrical tape around the exposed barrel will tighten her up just fine. Experiment with the amount of tape to get just the right snug fit...