[mythtv-users] NVCtrl: The NV-CONTROL X extension is not available on screen 0 of ''

[John Pilkington]

On 29/11/2019 23:59, John Pilkington wrote:
> I'm getting that 'Info' message on startup of mythfrontend, 2019-render 
> branch, in my el7 box that has no nVidia hardware.  Another box, Fedora 
> 30 with nVidia hardware is fine.
> 
> libXNVctrl version 352.21-2 is installed.  The codes of NVCtrl.h for el7 
> and f30 are identical.
> 
> I'm trying to track down a slow drift in a/v sync that I don't see on 
> other boxes, and this looks a vaguely plausible candidate.  I don't know 
> if the empty quotes are the problem or if it's something else.
> 
> 2019-11-29 22:31:22.691461 I  DispResX: Raw/unsorted XRANDR modes:
> 2019-11-29 22:31:22.691489 I  1440x900  75.00   60.00
> 
> $ xrandr
> Screen 0: minimum 8 x 8, current 1440 x 900, maximum 32767 x 32767
> VGA1 connected primary 1440x900+0+0 (normal left inverted right x axis y 
> axis) 410mm x 260mm
>     1440x900      59.89*+  74.98
> 
> $  mythfrontend -display VGA1 -v playback
> qt.qpa.screen: QXcbConnection: Could not connect to display VGA1
> Could not connect to any X display.
> 
> Any ideas?  Thanks,
> 
> John P

It accepts

$ mythfrontend -display :0 -v playback,timestamp --loglevel=debug

and later says

{{{
2019-12-02 20:33:34.758623 C  mythfrontend version: devel/2019-render 
[v31-Pre-4fbabd9038e] www.mythtv.org
2019-12-02 20:33:34.758638 C  Qt version: compile: 5.9.7, runtime: 5.9.7

====

2019-12-02 20:33:36.800732 I  Display: Found screen 'VGA1'
2019-12-02 20:33:36.800764 I  Display: Using screen 'VGA1' (Make: 
Unknown Model: Unknown)
2019-12-02 20:33:36.800796 I  Display: Geometry 1440x900+0+0 Size 
410mmx260mm
2019-12-02 20:33:36.801454 N  Display: Desktop video mode: 1440x900 
59.887 Hz
=====
2019-12-02 20:33:40.355486 I  Display: New main widget
2019-12-02 20:33:40.355503 W  Display: Widget does not have a window!
2019-12-02 20:33:40.355546 I  UI Screen Resolution: 1024 x 576
======
2019-12-02 20:33:42.147155 I  DisplayX11: Raw/unsorted XRANDR modes:
2019-12-02 20:33:42.147183 I  1440x900  75.00   60.00
2019-12-02 20:33:42.147199 I  1280x1024 75.00   60.00
====
2019-12-02 20:33:42.147302 I  640x480   75.00   73.00   67.00   60.00
2019-12-02 20:33:42.147315 I  720x400   70.00
2019-12-02 20:33:42.147395 D  NVCtrl: The NV-CONTROL X extension is not 
available on screen 0 of ':0'             ***********************
2019-12-02 20:33:42.148743 D  Setting 'Separate video modes for GUI and 
TV playback' changed to 0

}}}

.. but on this box, at this commit, driving this monitor, there's still 
a slow lipsync drift of order 1 second per hour.  I can detect it, but I 
haven't found a logging option that is convinced.