driver.get(urlstring) prints out DefaultCssErrorHandler object into console #230

I am working on a webscaper and as I am running ~30-100 threads, my console consists mostly of these lines:
com.gargoylesoftware.htmlunit.DefaultCssErrorHandler@6b15b6d8

I already attached the source code of htmlunit to the jar in my IDE but I havent found the reason while debugging.
It appears to print it out while being in the getPage method.

Is there a way to remove that?

The only way I found is to do System.setOut(null), but this disables everything and I still need some other outputs.