I have Google Merchant reporting broken links. The interesting thing is that the links they list almost all have the affiliate ID that I use to track sales through GM amended to them. What's going on here and how can I fix it?

How are they getting the information?
Is this through a feed? Is so, is the affiliate ID being added there perhaps?

Have you checked the broken links to see what's wrong with them, and confirm they are not working?

Thanks,
David

It is through a feed and, when I try to copy and paste the links, they work.

There are two ways to add that affiliate link. Assuming you are using Mike's (www.dlss.ca) feed generator.
You can add it in the feed, or you can add it in the google feed settings.
I used to add it in the feed, but changed to adding it in my feed settings.
Assuming you want it there, and you are currently adding it in the feed, maybe try removing it from the feed, and add it there in the google feed settings.

David

Thanks, I'll try that and see what happens!