This XML document is invalid, likely due to invalid characters. XML error: XML or text declaration n

Dear Support,

I get this error for some particular feed sources (not all). After some research, I understand that this should be due to the blank line before xml declaration of the source feed site and the site's owner should fix it. However, some rss readers are able to ignore this invalidity and allow me to get the feeds normally. I'd like to seek any possible way to get autoblog to ignore this and just process the feed anyway.