Hi, if a reboot doesn’t clear the V53 error this can be a signal fault.
I’m assuming the box upstairs doesn’t display this fault? If it does the thing both boxes have in common is the cable up the garden or the splitter it will be attached too
The coax cable Or connectors that carries the signal Could be damaged, or it could be that the connectors are loose.
if you have checked these then you could need a technician to investigate further.
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