Right then!
I finally managed to get to speak to someone at Tech Support, which took an hour in total. Forty minutes of that being on hold.. doh. But anyway, I explained about the downgrade (they said as far as they can tell I should be on 1.5Mbps) and the connection problems.
To cut it short: they put me back at 1.5Mbps and.. it fixed it! For a while anyway, as I just this second got booted off of MSN. When they bumped the speed back up, I was able to view websites and downloaded the DirectX runtime without any problems.
When this problem originally started on Thursday, the day before I kept getting kicked out of MSN but was able to use voice chat, play games, etc, without any probs. So going on that, I assume
Bad Things Will Happen(TM) tomorrow and
Really Bad Things Will Happen(TM) on Monday.
Oh yeah - my IP address is
81.108.83.*, by the way.
Edit: Forgot to say, I'm still at 1.5Mbps. I wasn't able to connect to the modem's status pages (is the silver Ambit a budget CM or something? Its status pages make me vomit blood everytime I see them) all today until I got whacked up to 1.5Mbps. My diagnosis of the whole situation is:
Summat's knackered, mother.
Edit 2: Also forgot to say that tech support said absolutely no-one else has reported this disconnection problem except for me. So I got the standard "It's your (crap) router!" about nine times.
Oh great - got booted out of voice chat. Yep, it's definately screwed again.