I have an Asus Scar 2 (GL504-GS model number) that has some audio issues. They started about three months in. The volume will randomly start fluctuating and it doesn't seem to matter what I am doing - gaming, youtube etc. I contacted Asus support to see what could be done. They had me uninstall and reinstall the drivers a few times, update BIOS and reset Windows. I ended up sending it in for repair which was a fiasco in itself that I wont get into (but will if you're curious). Once I received the laptop back a month later it was fine for two or three days and the issue is back. I am hoping for any help one can give thanks!