I need help with resolving an display issue. I have recently bought a old UST projector which has vga post only and wanted to connect my tv box and Google crome cast. I have active hdmi converter working fine with Google crome cast and laptop, but not working at all with ip tv box. Below is the link of active HDMI ro vga converter I am using.
The converter doesn't support HDCP compliant sources. Maybe your TV box is HDCP?
Try changing the video resolution of the TV box. You would need to connect it to a display to bring up the menu. Change it to the native resolution of the projector.