Note: I’m using a translator (Spanish to English) I’m sorry
I think I’ll help a little on this subject (the same thing happened to me)
USB ANT + Stick uses the same RF (Radio frequency) of 2.4Ghz as many other devices eg (Bluetooth, Wi-Fi Router, wireless cameras, smartphone, table, etc. etc.) and there is a lot of equipment that can cause interference They are in Your house and where the neighbor.
In theory it is assumed that these do not interfere with each other, but I am not deaf.
It is possible that for some reason you are having an interference problem, my advice is to get as close as possible the USB ANT + Stick from the center of the bike (under Crankset) and make a kind of Parabolic to concentrate the RF towards the direction of the sensors (Power meter, Heart Rate, smart trainer, etc.)
IMPORTANT: you must protect yourself from sweat (USB ANT + Stick)
Another important point is that the USB cable (USB exemption) is as short as possible (USB devices only support a determined length to work well) otherwise I recommend you use a USB Active Extension Cable (as short as possible)
Some photos as an example.
Option: adhesive tape to protect the USB ANT + Stick