If you have any headsets plugged in test to see if the sound is coming out of them. Else disconnect them.
You can set the Default audio devices by right clicking on the Speaker Icon at the bottom right, Playback Devices.
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Perhaps update the sound drivers. Likely from the motherboard manufacture or the computer's manufacture if pre-built, if it's a dedicated card then that manufacture.
If you get your audio through HDMI/DisplayPort then the sound drivers should be hooked in with the GPU drivers.
