nope, not sure. You could do a test run maybe? Just wash a couple in F&C. I know that it might be a PITA, but at least you'd know w/out having to possible strip ALL of your FB. Do you use Liquid or powder det. My fleece started stinking and repelling like crazy, got it cleared up now, but it seems like I remember someone told me that you shouldnt use liquid on fleece. So, maybe that was my problem.