Your local radio environment can be changing and you won’t notice a thing. For example, a local amateur radio operator can start a conversation near 433.92MHz and obliterate your signal every time they key the mic and talk.
Radio interference kills your signal as it makes it hard to separate the signal from the noise.
Again, I suggest you start by putting a ferrite bead on your USB cable. They are cheap and can’t hurt.
Should that not work, look for local sources of possible noise. As electronic systems age, they can start spewing noise and you won’t notice a thing. For example, a nearby dimmer switch might be going bad and throwing noise, however, from your perspective it will seem to be working just fine, and may continue to do so for months or years.
Sent from my iPhone using Tapatalk