Having mixed luck with Time Machine

I have a new 2TB Time Capsule, having shelved a TC once before because I could never really get TM to work reliably. Knock on wood, I've never needed to restore, but last week I got the new TC in hopes that it was worth another shot.

I'm on an iMac 27 running Lion, and I have my machine cabled to a separate router on the ethernet port. I then use the Airport to connect to the Time Capsule's network, and for a few days, all was well.

Tonight, I noticed that my hourly backup was taking an extra long time, and it was stuck at 2MB. The log shows this:

I gave it some more time, and ended up having to kill backupd from the terminal. Now I've rebooted, and it appears that my sparse bundle is corrupted. Nothing shows up in Time Machine, and the backups still don't run.

I've always had great luck pairing Apple gear with other Apple gear, but now this is my second Time Capsule that's been a hassle after only a day or two. Am I missing something here, or am I doing something wrong?

The only anomaly in my setup is that I don't want to use the TC for a wireless router. That said, I DID use my first TC for a router, and ended up having the same problems. (stuck backups, Time Machine hanging, etc). At present I can't even eject the TC volume.

Edit:

Had to hard-reboot, did a factory reset on the Time Capsule, reset it up from scratch, and it's stuck at 2MB again with the same error.