Hijack v420 has no obvious effect. It's still rebooting ad infinum with the same hijack messages flashing up.

In answer to the 1st reply, I did try initially reverting back to hijack 417, but it just rebooted with no error messages, but it did take slightly longer to reboot. I noticed that it had lost it's position and wasn't showing a current playlist just before it rebooted.

When I was getting the hda messages earlier, they were appearing on several different tracks, so I don't think it's one specific song that's causing the errors.