I couldn't easily find any other sites using link units at first, so I had nothing to compare it to, but now that I have found one the problem seems to be limited to my site, not my browser.

The link unit on my site is in a float: right, which I suspect may be the cause of the issue. The peculiar thing is that it only seems to affect link units; other ad formats work just fine when I let them float to the right. And, like I said earlier, it also works fine in Internet Explorer.

Odd. Perhaps I'll have to use relative or absolute positioning instead of a float, see if that works.

Try putting the adsense code in it's own div, and then float that div to the right, rather than floating the adsense code itself.

<div style="float: right;">adsense code</div>

That's basically what it looks like.

Does anyone have any ideas or suggestions? Using positioning seems to ruin my layout.

A strange necessity to have to work around it like this, but it now seems to work in all browsers.