Volume issue with WACO YMF5

Several times the game is not visible. i have to delete and reinstall. WHY now after reloading i have no volume?

You say you have no volume, does that mean you have no sound at all?
Did you check to ensure that in MSFS General Options, if you have these set.

The top two should be set to what you have selected in your system’s Windows options.
Unless you are using the headphone simulation (which blocks most sound other than what a pilot would hear in his headphones - basically just communications), that should be selected “off”.

If the above are selected properly, that could be more like a PC issue rather than MSFS.