I added a cron job to one Pi that checks if wifi is up and tries to restart it if not. I also had an LG monitor that had so much feedback it would disable the

I added a cron job to one Pi that checks if wifi is up and tries to restart it if not. I also had an LG monitor that had so much feedback it would disable the WiFi interface completely. So I would check your monitor, if the pi is connected to one.