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It's worth trying a reset to factory settings and seeing if that makes a difference. Then make sure you have powered off modem, router and PC, before restarting modem, router and PC in that order, having let each settle down before powering the next.
If this doesn't work, I note you have a new modem connection instead of PC. I assume you have setup that modem connection and you are happy it works with a direct modem to PC connection? Did you use the virgin media disk to do this? If so did that disk affect any settings for your network connection on the PC, or Internet Explorer?