What should I do about goTranscript?

I have been invited to one of their projects lately, but man, the audio quality is so horribile, I just can't begin to describe... Over the last two days, I managed to transcribe ONE task, because out of 50-something available all that I checked are either audios with like 5 or 10 people talking at the same time or constant background noise with some muffled speech. I'd accept it if it was just one or two tasks that are awful, but here it's almost the entire batch.... I have experience transcribing for other sites, but here I just can't tell what people are saying :/ . Should I just give up and contact their support or transcribe them all as errors? Is it even possible they didn't notice that? Maybe there's something that I'm doing wrong?