Try Pressing Stop and then press Play again - do you get sound straightaway ?
On one of my PCs (but not the other) I sometimes get a 2 second silent playback with the playback meters bouncing - and then the audio cuts in, I have a suspicion that it is something to do with the soundcard driver.
I particularly notice this when I leave Audacity for another app and then go back (in fact I left writing this just now to try and lo and behold the silent 2 seconds then normal audio output).
See this other thread posted recently: https://forum.audacityteam.org/t/2-second-delay-on-first-playback/53310/1
This particular PC of mine (an SSD HP Envy with W10) also has another oddity - this time with record where it fades itself in over the first two seconds and then normal levels are achieved. I think that this too is the soundcard driver software trying to be “helpful”.
Update: Argh - testing this recording “feature” I now find it’s gone away - maybe the dricer was updated as part of a Windows update - who knows …
My HP Probook with W10 does not exhibit these “helpful features” and nor does my Macbook Pro running Mojave.
Peter.