Since you didn't give us the make and model of the computer, and you stated that you "Took the keyboard out", it's only a guess that you're using a laptop.. If it is a laptop, the spill could have dribbled down into other parts of the computer, maybe the motherboard, or very possibly the sound cable from the keyboard to the sound card. Heck, downloading and installing an updated sound driver might rectify any glitches that were caused by the short.
Or, if it's an external sound cable, try replacing it. If it's an internal cable, you may need a repair person to take a look at the internal parts for damage, such as the motherboard, or the sound card itself.
Hope this helps.
Grif
Windows 8, haven't had this issue ever and recently started 2 days ago. I spilled water on my keyboard on accident, which had my headset plugged into it. Took the keyboard out and dried it so that it would work again. The keyboard operates as good as new but now when I alt tab out of a full screen, my sound for everything in the entire computer goes mute.
I can't get the sound back unless I restart the computer. Once I restart the computer, the sound works fine.
I've replaced my keyboard to see if that's the issue, it's not. Im fairly dumb when it comes to computer issues so I don't know many other fixes or options. I'm assuming since the keyboard shorted out it caused a hiccup in my system, not sure if it's correctable or not.
Thanks for any and all help!

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