As previous reply, you need to test speeds with a laptop or PC, directly connected to the Hub with a Cat 6a cable. The device must be capable of a 1Gb connection.
What does a speed test at www.samknows.com/realspeed show ?
Also you could try a full factory reset on the Hub as below;
Remove any ethernet cables from the Hub and hold the pinhole reset switch for 60 seconds. Do NOT reboot the Hub, just let it do it's thing. Note you will need the passwords from the bottom of the Hub afterwards, so make sure they are legible.
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