Windows 7: Interesting issue when scanning for new channels

My cable company recently changed their lineup, and for the analog channels everything works fine. However for the digital channels it only finds one of what should be 20+

When I watch the scanning process (what a yawn fest!) I see other channels pop-up and then disappear, sometimes 2 or 3 at a time... So it looks like for some reason the scanner is finding them, then discarding them.

Any ideas?

My Media Center is Version:
6.1.7601.17514(win7sp1_rtm.101119-1850



My tuner is a Hauppage Win TV-HVR-2250

Everything used to work, but the last time I scanned was before the SP1 update.