Hello i need groovymame help

[Immortalhate666]

So i follow the guide on andys youtube,,
I have a dedacted mk4 cab with a crt in it so i switch type to arcade 15.7 in vm maker and do my configs in there i enable
The EDID emulation mode the lcd screen turns black i hook tje jpac up to my arcade crt tube and i get nothing but a black rolling screen? Not even windows...since the drivers in emu mode now when i hook back to the lcd to see i did wrong its just a black screen to fix i have to put in vga mode to diable the gpu crt driver..also byw im using a old jpac not the newest one with the usb plugin..i just want this to work on my crt tube thanks guys.