After about a week of waiting my XLS200 arrived today! Hooray I left it on for a few hours to let itself run in etc. I then came back to it, turned up the volume a bit and the bloomin thing is rattling (just like the sub i returned about 2 weeks ago ) Apart from that it really does sound great. What the hell should i do? When I press on the heatsink, the rattling stops, so something is definately loose. Shoud I tighten the screws? Will this invalidate my warranty? I will not open the sub up so please dont ask me too!! If you want i can upload a small audio clip of the rattling. To me it sounds like the rattle is coming from the bottom right part of the metal plate at the back (i guess where the transformer is). Any help would be greatly appreciated Tim.