Download problems

Hello all

Until two weeks ago my system had been completely stable for about 6 months. Now, all of a sudden, downloads drop out intermittently, usually between 5 and 15 minutes. My carrier assures me (after several line checks) that none of my line conditions have changed and that I have a good connection. I have no viruses (NOD32), no Spyware (Spy Sweeper) and my registry is clean (Registry Mechanic). I run Zonealarm and get very few attempted infiltrations. No new software has been added in the last two weeks. I run XP Pro. I have reset defaults and rebooted my ADSL MODEM several times.

Interestingly enough, FTP uploads (Core FTP) also fail regurlarly.

I've run out of ideas. Any new ones would be appreciated