My list of things that worked to get playback for MS4 on Windows.
Aren't we all just having a blast with MS4. Just kidding. If you are having trouble just getting it to play, try the following.
Read the minimum specs required to make MS4 play correctly. They make a difference. Only one of my computers has those specs, and MS4 works fine on it. The others I’ve been able to get acceptable playback by doing some or all of the following. Bear in mind that the only spec my other computers lacked was the 4 core CPU.
Turn up the buffer in Preferences I/O. And make sure your best Audio Device is chosen. Not System Default if you have a choice.
Right click on the speaker icon in the taskbar. Select "Sounds". In the popup select "Playback". Make sure the audio device you are using in MuseScore is checked in this window. Click next to the icon and select the "Properties" button. In the new popup, select "Advanced". Here you can uncheck "exclusive Mode" and also take the bit rate down a notch.
As a last resort, I have to use my audio interface on one of my computers. Mine is a Focusrite Scarlett.