We've tried different configs including 300mbps, 150mbps, 2.4Ghz & 5Ghz and have tried different security encryptions... Enabling 300mbps or 5Ghz band renders 802.11g devices useless

. Virgin have also fiddled around at their end and always stick to the script when you call them (tell you to reset or power off the superhub for 30 seconds etc... Usual stuff.). Many Virgin customers are suffering with these poor qaulity hubs at the moment

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Options are pretty limited when it comes to setting these things up (it usually gets done automatically from their end).