[mythtv-users] Live USB2 for HD-PVR Captions

Stephen Worthington stephen_agent at jsw.gen.nz
Mon Jan 3 16:34:25 UTC 2022

On Mon, 3 Jan 2022 08:45:42 -0700, you wrote:

>Trying to following the guide here: 
>Using Hauppauge Live 2 USB device with Debian 11 (5.10.0-10-amd64). The 
>device nodes have been created automatically. However, when I try the 
>command below I get an unexpected error:
>$ v4l2-ctl --get-fmt-vbi-out -d /dev/vbi3
>VIDIOC_G_FMT: failed: Invalid argument
>FYI - I have 4 VBI devices and I get the same message for all of them.
>Kernel seems to recognize the device, not sure what "Alternate settings" 
>[255695.468609] cx231xx 2-1.4:1.1: v4l2 driver version 0.0.3
>[255695.568600] cx231xx 2-1.4:1.1: Registered video device video4 [v4l2]
>[255695.568662] cx231xx 2-1.4:1.1: Registered VBI device vbi3
>[255695.568831] cx231xx 2-1.4:1.1: audio EndPoint Addr 0x83, Alternate 
>settings: 3
>[255695.568834] cx231xx 2-1.4:1.1: video EndPoint Addr 0x84, Alternate 
>settings: 5
>[255695.568837] cx231xx 2-1.4:1.1: VBI EndPoint Addr 0x85, Alternate 
>settings: 2
>[255695.568840] cx231xx 2-1.4:1.1: sliced CC EndPoint Addr 0x86, 
>Alternate settings: 2
>I went down this rabbit hole trying this command to make sure "CC" would 
>$ v4l2-ctl -d /dev/vbi3 --set-fmt-sliced-vbi=cc
>VIDIOC_S_FMT: failed: Invalid argument
>Do I need to get a different device?

Did you install the Hauppauge drivers as per this page:


or are you working with the normal drivers in the standard kernel?

This page looks to have a lot of useful information:


There is a test tool for v4l2 devices: v4l2-compliance.  But if it
fails, you really need to get the latest git version of it and compile
that as the man page says that the versions distributed with distros
is usually too old:

man v4l2-compliance

You say that you have four VBI devices - where do they all come from?
There should only be one from the Hauppauge Live2 as it has only one
input.  You can tell which one the Hauppauge Live2 is by unplugging it
and plugging it in again.  Then the dmesg command will show what
devices get created when you plug it in again.

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