If you open more than one auction at a time, all the image pages show the same item. Look at the link to it, and it's always to the same page, http://www.spheremusic.com/Bargainimgdsp.asp -- with no parameters.
Open it in a new tab, and it shows the last item whose auction page you viewed.
They must be setting a cookie or something in the auction page, then reading it in the image page. That's actually a bigger hassle to code than doing it right.
I hope they didn't pay anybody very much for their shiny new site. If they did, they got ripped off.