What's the first thing to get knocked off a 412VS-T at a gig? Right, the rubber feet. So why aren't they listed on the line6 parts pages??? Where can I get a replacement foot? Why does my 412VS-T have rubber feet, when the product photos on the website all show casters for that cabinet? Why aren't replacement casters listed on the parts page? Can I replace the cheap rubber feet with casters? How do I order them?