USB C port no longer able to output to external monitor

General system Kernel, boot, graphics & hardware
1

I have been using a usb c to display port cable for a while. However, recently, the port I was using stopped working. To clarify the port seems to work for data transfer and charging of devices like my phone, but is incapable of displaying to my monitor. The thing is the other usb c port (which is the one I use for charging) on my laptop works fine with the monitor.

I have tried both the usb c to display port cable I was using before and I purchased a new usb c to HDMI adapter. Neither work on the non-functional monitor port and both work while using the charging port.

Any ideas would be greatly appreciated, thank you.

2

I would think it might be the cord but am only guessing about this

3

Thank you for the suggestion and I thought that as well, but the second connector I bought (usb c to HDMI adapter) also only works in one port and not the other. I may still buy another cable, but I don’t understand why both cables I have tried would fail in the same way.

4

Perhaps you could try to connect another monitor, to see if that is working with the heb c cable? That would rule out a problem with the monitor rather than the usb c port.

5

Just to help rule things out are you able to share more on what you have bought, some cables are honesty just shit like the 1 currently charging my phone, try use with PC and it is useless but for just charging works as expected.

6

I don’t have another monitor with a display port input, but using the usb c to HDMI adapter I get the same results (i.e. working with one port and not the other).

7

They are admittedly both rather cheap. The old usb c to display port cable is Pluggable brand, I believe. And the usb c to HDMI adapter is ONN brand.

8

I would go back and check how each where advertsed and make sure they are capable

9

Well the usb c to display port cable had been working for over a year, so it must be capable, right? And given it still functions on the other port and the new cable is experiencing the same results (and on a different monitor) it would be surprising if it were the cables would it not?

10

True, sorry. Have you tried it with a different kernel?

(Just so you know i ain’t an expert just going through things i would try

11

Yes, I have. Standard. LTS, and zen.

No problem, I appreciate the help!

12

does the port itself work with anything else? I mean if the cables are working then that would be the next best place.

13

Yes it does, worked with my android phone for charging and I was able to backup my laptop to and external drive using the port.

If you are interested here is the output of journalctl -f when plugging in the usb c to displayport cable

Nov 11 00:31:02 sf-latitude kernel: usb 3-2: new full-speed USB device number 23 using xhci_hcd
Nov 11 00:31:02 sf-latitude kernel: usb 3-2: New USB device found, idVendor=06c4, idProduct=c100, bcdDevice= 0.04
Nov 11 00:31:02 sf-latitude kernel: usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Nov 11 00:31:02 sf-latitude kernel: usb 3-2: Product: DisplayPort ALT mode device
Nov 11 00:31:02 sf-latitude kernel: usb 3-2: Manufacturer: BizLink Technology Inc.
14

nvrmind I see you say

I originally thought the journal was about the android

what DE?

15

Yes sorry, I should also clarify that is the output when plugging in to the port that is not working with the monitor.

16

do it with the monitor.

17

Niri, so I am using wayland.

Apologies, I am not sure what you mean.

18

show us the results of
journalctl -f when you plug in the monitor to the port that is giving you issues.

19

Those are the results from the problematic port.

The functional port actually didn’t output anything like that. Here is what the functional port showed:

Nov 11 00:33:59 sf-latitude niri[1995]: 2025-11-11T05:33:59.342638Z DEBUG niri::backend::tty: device changed: 57857
Nov 11 00:33:59 sf-latitude niri[1995]: 2025-11-11T05:33:59.389342Z DEBUG niri::backend::tty: new connector: DP-1 "PanaScope Pixio PX248P 0x00000001"
Nov 11 00:33:59 sf-latitude niri[1995]: 2025-11-11T05:33:59.389448Z DEBUG niri::backend::tty: connecting connector: DP-1
Nov 11 00:33:59 sf-latitude niri[1995]: 2025-11-11T05:33:59.389479Z DEBUG niri::backend::tty: picking mode: Mode { name: "1920x1080", clock: 148500, size: (1920, 1080), hsync: (1968, 2000, 2200), vsync: (1083, 1088, 1125), hskew: 0, vscan: 0, vrefresh: 60, mode_type: ModeTypeFlags(PREFERRED | DRIVER) }
Nov 11 00:33:59 sf-latitude niri[1995]: 2025-11-11T05:33:59.395140Z DEBUG niri::niri: putting output DP-1 at x=3286 y=0

So maybe an issue with wayland or niri?

20

Possibly, I don’t use either so maybe someone has some ideas.