Default Issues with data connection dropping

At the moment although I'm not on a 4g plan I currently get amazing speeds on dc-hsdpa and this is displayed as "dc" next to my signal bars, however everytime it drops to "h" (assuming hspa or hsupa) my connection fails instantly and I can't load a single page till it goes back to dc-hsdpa. It only seems to happen in the area I live in really but it really is causing problems for streaming and Web browsing. It switches between the 2 bands constantly and very occasionally will pick up h+ but I can't understand while on h it doesn't seem to connect to anything? Sometimes it's so bad that I have to switch data connection off/on again! Any ideas? So frustrating!

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