iTunes won't download song purchases on one of my Macs

[rockinrocker]

I've tried un-authorizing and re-authorizing and it doesn't help.

When I got to songs I've purchased in the store the tab says "Purchased" but there's no option to download them.

When I click 'Check for downloads' it says there aren't any available.

Apps work fine, everything downloads to my other computer and iStuff fine…
Is there anything else I can try?

Thanks