Thousands of listeners have posted on the internet claiming that a version of the record on video game Guitar Hero is an improvement.
However, drummer Lars Ulrich insisted that any complaints have been blown out of proportion, arguing that the record sounds "smokin'".
"Listen, there's nothing up with the audio quality," he told Blender. "It's 2008, and that’s how we make records.
"[Producer] Rick Rubin's whole thing is to try and get it to sound lively, to get it sound loud, to get it to sound exciting, to get it to jump out of the speakers.
"Of course, I've heard that there are a few people complaining. But I've been listening to it the last couple of days in my car and it sounds f***in' smokin'."
He continued: "The internet gives everybody a voice, and the internet has a tendency to give the complainers a louder voice."