Its possible that the Hub as an intermittent fault on wifi, but much more likely you are suffering from poor wifi in your environment.
What diagnostic checks do you need other than devices dropping out whilst ethernet cables remain connected? VM Pods are not a great option, get your own better quality wireless equipment and you will soon recoup the Pod rental charge.
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John
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I do not work for VM. My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router +2 Airport Express's. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.