Had a weird problem recently, related to RFI.
My station is a IC-7300, MacBookAir, and a Apple ThunderBolt 27" display. USB 3.0 hub with printer, backup disk, and IC-7300 connected.
Running WSJT-X 2.1.2 in FT8 OK up to about 60 watts but shuts down after that. Squeal in speakers, IC-7300 reboots. Then I switched to FT4, major RFI, and it is unusable. Squeal in speakers, IC-7300 shuts down.
I experimented with a number of RFI solutions, but the fix was clamp on toroids on ALL leads going to USB hub and to/from Monitor. That is the DisplayPort, power to MacBookAir and the 110 volt power cord.
Now both FT8 and FT4 now work fine.
Got a box with several different sizes of RFI clamp on toroids on Amazon for about US$10.