I haven't had to print a label since Friday, so can't say if it's happening to me or not. However, I do download and save the labels to a folder "ebay labels", with the buyers name as the name of the file. That way if I do need to reprint for whatever reason, I can just open the .pdf file and reprint. Only had to reprint once when it came out smudged. I delete the file after 6 months.
Edit: have you tried the usual fixes, of clearing out cookies and cache? That fixes a multitude of eBay problems. Make sure when you clear you clear for all time, not just the last month (which I think is the default).
