I have tried rebooting and reinstalling the app but the problem doesn't change.
If I open task manager and look at the running processes I see that Yousician appears to be running properly with not unusually high resources used.
This is on a Lenovo Yoga 920 laptop. I have used the app on the PC for a few yrs.
Uke: Complete Lead (perfected L5), Complete Rhythm(perfected L6)
Bass: Complete (perfected L2)
Piano: L5 Classical (perfectedL2), L4 Pop (perfected L2)