Suddenly midi delay about 300ms

Hello, i have now a Midi delay on some tracks. About 300ms from pressing a key to sound comes.
Does anyone know what the reason could be?

It’s only on one project. On others all ok.

I found the reason - one or all 2:

  1. Restart my dektop
  2. I removed a 1 GB SF2 File (GM File) - played with ACE Fluid Synth (exportet the one sound with linux polyphone as SFZ and play and optimize it now in Redux.