Here's a weird one...

I just bought an Anthem 225i Integrated amp to rum Maggie 1.7s. I like the amp a lot but it did something scary the other day. I was just adjusting volume with the remote, and the volume just kept increasing. By the time I was out of my chair and across the room it was maxed out! The amp would not respond to the remote, OR to manually hitting the power button! I turned the volume knob down but it kept trying to go back up. I finally had to kill power to the amp. When I fired everything back up, all was normal, and it hasn't done it again. No damage, luckily, to the speakers.

Anyone experience anything like this? Any thoughts?
Yep - welcome to the wonderful world of DSP controlled processors. Your problem illustrates why I really like preamps/processors that have a Max Volume setting. This also helps to keep the babysitter's boyfriend from frying your speakers...

Happened to me once with a Bryston B100SST. Never happened after that.
Have a look at your remote. Sometimes if you push a button down a little too hard or at an angle, it will get stuck underneath the face. It happens all the time with my Wadia remotes. The rubber buttons have a hard time sliding when they come in to contact of the metal used to make the remote. That's probably what happened to Xti16's Bryston. I'm not too familiar with the remote that comes with the Anthem, but its worth looking at. It drove me crazy until I finally figured out what was happening.
Argh!! It just did it again, but this time with the volume staying all the way down. I thought about the remote too...I don't THINK it's that but who knows...
You can check it. Play with the volume buttons and see if you can make them stick. If you can't, its probably not the remote.
Good thing for me it only happened once.
So, as usual, trying to buy something from a North American based company results in buying junk. Sad.
If it happens again try turning the remote away from the amp or better yet if possible remove the battery while it's happening and see if it stops. If it does then it's the remote.
I emailed the company. They wrote back that it needs to be serviced. Brilliant, eh?