So I just got my receiver back from the shop. Previously, I couldn't switch any inputs so they had to replace a switch inside. I just plugged everything in and noticed that my Xbox and Cable was shaky. If it matters...it shakes up and down not left to right. Most noticeable on still frames rather than action shots. After some troubleshooting, I narrowed down the issue:

When viewing 1080p or 1080i using Component cables, the screen is shaky.

I changed the sources to 720p and they look fine. I know it's just the component having an issue because my 1080p BluRay player looks great, with no shakes, using HDMI.

If I bypass the receiver and run the component to my Samsung TV, there are no issues. I'd send it back to the shop but I have to ship it (no Onkyo service center in Jacksonville).