No sound on computer only in Audacity

Hello i dont know IF its new bug but couldnt find it i got it just after i downloaded Audacity. I put in an mp3 and starter looking around i then i wanted to look on a beat on youtube and i had no sound nethier on Audacity. Then i restarted my computer and then the sound only worked on Audacity but not om my computer. I restarted a couper of Times’ but couldnt find a solution im not so good with computers ethier so can someone pls help

Audacity shouldn’t change your computer configuration.

Did you plug-in a USB microphone or some other USB device? …Sometimes Windows tries to use the “new” USB device as the default soundcard.