Thanks for running the tests. Insight sent a tech out today. He rang the doorbell, and told me they'd been replacing cable in the area the past couple weeks, which correlates with the time since my trouble started. He said he'd looked at the line and everything looks fine now; they don't see any problem on the line. I know firsthand how near impossible it can be to track down something like this and fix it, and now that I finally have options, I think I'll just switch to AT&T. Anybody else on here use them for broadband?