MaliceX wrote on Today, 16:06:

Given the CPU usage I doubt an era-accurate PC from WinXP or earlier days would be able to play music with S-MU2000 in real-time 😁

Yeah I noticed that CPU-usage too, after writing that. MU2000 has one 3,5GHz core 90% saturated, two other cores approx. 60%.
There was a commit today about limiting the amount of slave threads proportional to the total core count. Have not tested that yet.

Mine is not an era-accurate system.Still, browsing while playing midi gave sound hickups at times.
Have to check how it compares against Mame MU50 in that regard...