I have always had the following error message with 2019 on opening. "Windows audio session error, could not open bitstream. error -9997". (Is this the same error or do I need a new thread?) The error message disappeared after about seven seconds and did not affect the operation of the program. It was suggested by someone a few weeks ago and above in this thread, that it may be because the audio driver type was set to WAS. In my case this was the case and switching to MME solved the error message problem. However switching to MME introduced a lag in the editable notation window which was not there with WAS. I.e. clicking on the staves to insert a note did not result in the note sounding immediately. Not a large lag but enough to be an irritation. All other playback elements of the program with MME are perfectly in sync as they are with WAS. I can enter the notes quickly and this effect does actually slow things down. As things stand I can easily live with the error message and stick with WAS. I can see no obvious way to correct the lag with MME