我有一台连接到 Dell WD19B 扩展坞的 Dell XPS 13 9310 笔记本电脑。我有三个屏幕连接到扩展坞 + 笔记本电脑屏幕，出于某种原因，所有屏幕都被检测到，Ubuntu 表现得好像所有显示器都在工作，但其中一个屏幕始终显示“无信号”。
有什么办法可以让四个屏幕同时工作吗？或者这是 DisplayLink 的问题？
这是 xrandr 的输出，似乎也表明所有监视器都在工作
Screen 0: minimum 16 x 16, current 7680 x 1200, maximum 32767 x 32767
XWAYLAND0 connected 1920x1200+0+0 (0x28) normal (normal left inverted right x axis y axis) 290mm x 180mm
Identifier: 0x21
Timestamp: 767795
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 0.0
Clones:
CRTC: 0
CRTCs: 0
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
non-desktop: 0
supported: 0, 1
1920x1200 (0x28) 193.250MHz -HSync +VSync *current +preferred
h: width 1920 start 2056 end 2256 total 2592 skew 0 clock 74.56KHz
v: height 1200 start 1203 end 1209 total 1245 clock 59.88Hz
XWAYLAND8 connected 1920x1080+3840+0 (0x29) normal (normal left inverted right x axis y axis) 600mm x 340mm
Identifier: 0x551
Timestamp: 767795
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 0.0
Clones:
CRTC: 1
CRTCs: 1
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
non-desktop: 0
supported: 0, 1
1920x1080 (0x29) 173.000MHz -HSync +VSync *current +preferred
h: width 1920 start 2048 end 2248 total 2576 skew 0 clock 67.16KHz
v: height 1080 start 1083 end 1088 total 1120 clock 59.96Hz
XWAYLAND9 connected 1920x1080+1920+0 (0x29) normal (normal left inverted right x axis y axis) 600mm x 340mm
Identifier: 0x553
Timestamp: 767795
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 0.0
Clones:
CRTC: 2
CRTCs: 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
non-desktop: 0
supported: 0, 1
1920x1080 (0x29) 173.000MHz -HSync +VSync *current +preferred
h: width 1920 start 2048 end 2248 total 2576 skew 0 clock 67.16KHz
v: height 1080 start 1083 end 1088 total 1120 clock 59.96Hz
XWAYLAND11 connected 1920x1080+5760+0 (0x29) normal (normal left inverted right x axis y axis) 480mm x 270mm
Identifier: 0x55c
Timestamp: 767795
Subpixel: unknown
Gamma: 5.3:inf:-0.66
Brightness: 0.63
Clones:
CRTC: 3
CRTCs: 3
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
non-desktop: 0
supported: 0, 1
1920x1080 (0x29) 173.000MHz -HSync +VSync *current +preferred
h: width 1920 start 2048 end 2248 total 2576 skew 0 clock 67.16KHz
v: height 1080 start 1083 end 1088 total 1120 clock 59.96Hz