It looks like you're not on the newer DOCSIS 1.1 256QAM network which may be causing issues with utilisation in your area. Before I was migrated to the newer network, the maximum speed I would get was 13mb most of the time, only the odd 20mb speed. Since I have been migrated, I always hit 19mb+, so that's what needs to be done in your area (I don't understand why it hasn't as I thought all 20mb customers were being switched). My current speed is:
and that is wirelessly, I would never get anywhere near that before they changed the UBR I was on apart from after 12am as in my sig.
All I can suggest is that you either drop to 10mb or you upgrade to 50mb where you will definitely be on the new UBR AFAIK.
Ben
