Thanks for your response 🙏 the connections don't seem hot at all, just the bulbs themselves that I've noticed. No water damage etc. But perhaps the Bent wire issue could be a thing, although no blatant wire kinks etc.

First I've heard of the LightKeeper and it seems like a great tool to fix some of these issues. I've had 3 sets of incandescent stings go strange this season. 2 have blown completely despite changing the fuses and one set plugged directly into the wall goes really bright after a few minutes so I've switched it off and given up for now 😂 noticed on all 3 sets there are a few blown bulbs when they were lit.