I had this issue with old gen Unifi SFP+ to RJ45 10Gbe, 3 failed. Needed gloves to remove them. Bought newer gen and they are warm but i dont need gloves.
The difference between fiber module and RJ45 is massive. I found it funny that Ubiquity own switches (at least my Enterprise 8 PoE - the one they call "vintage" - I kid you not) will set the fan default to 35 (whatever that value means) if you use SFP+ RJ45 module (regardless of temps), and have fans at 0 without the module, when the switch is below 75 celsius.
Ironically, one of my switches with the RJ45 module runs cooler than the one without because Ubiquity does not let you do any fan control on Unifi Enterprise 8 PoE.
