Hi i have question about taking a screenshot from telnet (putty)

I get this error when trying to grab a screenshot

root@dreamone:~# grab -o -p /tmp/grab.png
AiO Dreambox Screengrabber 0.95

Unknown STB .. quit.

Is this DreamOS issue or is AiO Dreambox ScreenGrabber added by Team Dream-Elite?

As you can see from the error i use a DM One UltraHD with Dream-Elite7