Hot Key Combo seems to have killed all audio

Hi Guys,

I've hit some combo of buttons and it muted all of my clips. No mute buttons are lit up. Audio works on other projects other projects. The tracks all have that slightly grayed out look you get when they are muted, but again, no mute buttons are lit up, and I've toggled them off and on.

The only thing that seems different from a project that will play audio is the in the track window under clips, (where you get the Apply Trimming, and Bounce to Clips options, all of the options are grayed out, as where on a working project they are obviously working, that is not grayed out.

Like I said, I think I hit a short cut accidentally but I've no idea what I've done.

Any help would be appreciated.

Thanks

Do you see the red mute (circle with slash through it) in the upper left of each waveform in track view? If yes, you can select a track and press "K" to toggle the mute. Or you can use the mute tool and left click the track with the mouse. 
 
Another idea is that if the tracks were froze while muted they would appear grayed out and the "bounce to clip", etc, would be grayed out and inaccessible.
The snowflake button (asterisk) would be blue if they are frozen.