A couple of weeks ago I took one of my 5" crossfire quads to a bando and proceeded to micro failsafe myself onto a roof - at least it felt like a micro failsafe. 

Today I took the same quad to a park and had it randomly happen again.  LQ didn't drop at all in my goggle feed during the event, but in the video I lost control going between the trees, then frantically tried to throttle up.  It seems like I had tiny dropouts during the throttle increase, which made it sound like my quad was singing.  Could this be failsafes or something else?

A few years ago that would have likely been the TX throttle potentiometer having a dirty track! :-)

Near impossible to comment accurately without more detail on equipment, but :-

1. Test if its limited to ONE quad only - so eliminate Tx
2. Establish if its distance related

A blackbox log should tell you. This is why I permanently run blackbox logging on any quads that support it, so I can do some post flight analysis if anything odd happens during any of the flights.

As far as it being distance related, I flew back in that same area another few times to test and it didn't happen again.

A couple of months ago I had this issue with a micro and Snow recommended ExpressLRS. I switched the micro to that and had no issue since. I'm going to switch this one as well and see if that happens again.

One thing both this quad and that micro have in common is they run Fettec FCs, so I can't run a blackbox on them, even externally. Was super disappointed when I found this out, so I'm ditching anything Kiss related as soon as these FCs take a dump.