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If so then I would try entering the Hub manager and selecting manually a channel for it to use rather than letting it pick one automatically. The BT speed check will measure the result to the Hub, the on-line one will measure the speed you see at your device which can be impacted by interference.
Try something like Channel 1 or Channel 6 or 11 first.
There will be details on the Web on how to do this for whatever Hub you have. It only takes a minute to do.