playstation 3 question?

Ok here is the deal and I am really puzzeled. Over the weekend I was playing my PS3 online, all pro football 2k8 to be specific and I wouldn't let me play online becasue my framerate or something was incorrect. I didn't know how to change it so I went to the XMB and went to system settings and enabled the ATRAC. Whatever that is I don't know. Now my sound is absolutley horrible. When the crowd cheers is is just static. I thought that my HDMI cable went bad so I bought another one. Same problem. So I switched to the other HDMI port on my TV, same problem. In an act of desperation I plugged the standard hook up in and turned in on. Well other that the graphics sucking(which I knew would happen) the sound was perfect, so now I am led to believe that the HDMI port on my PS3 is bad, what do you guys think?