Using WiFi on the RPi 3B+ is independent of the USB bus and may be all you need to fix your dropouts and glitches.
Just to check, your USB Disk is self-powered and not powered from the Pi USB ?
Shared power can be a source of problems describe too.
Image of the Pi3 showing the separation for WiFi and Ethernet/USB.
Just to check, your USB Disk is self-powered and not powered from the Pi USB ?
Shared power can be a source of problems describe too.
Image of the Pi3 showing the separation for WiFi and Ethernet/USB.
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bob
bob
