Today I slung my camera over by back and after a few seconds, felt it shift in a way that I knew was a problem. The glue that I had put on the flash had failed, and it cracked open, exposing the wires. One of the wires is now disconnected.
The flash itself fires when I hit the test button, but it is not fired off by the camera because of the loose wire. I don't have a sodering kit, so I plan on taking it to a shop somewhere to get the wire sodered. If I take it to Canon, it will take weeks and cost a fortune, and I think the risk of having it fixed is pretty small.