Yeah, I'm going crazy with this. I noticed that my devices periodically were not available for a few minutes at a time. After using wifi analyzer, I noticed that the signal just VANISHES periodically but very regularly.
I was using a Netgear Nighthawk R8500, and thought it might be faulty, so replaced it with a TP ArcherC5400X... but the problem continues in the exact same way! The 5Ghz network and hardwired devices are rock solid. I updated the firmware then factory reset both routers.
I noticed that it's ALL the 2.4Ghz signals around, across all different internet providers. The signal drops also cycle through the channels. IE the channel 1's go down and come back, then channel 6 and then 11.
There is a new construction site not too far away, but I wouldn't know what to ask them to look into.
Here is a sample of the signal:
Any help would be greatly appreciated figuring out what kind of device would cause such interference.