This is pretty similar to audio issue we've encountered before. Could you open sound setting and play test sound to see if this issue happens while playing sounds?
BTW, could you also check if it lists the same audio output devices when the dock cable is plugged at left side and right side. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1884001 Title: [Ice Lake] External 4k monitor periodically shows black screen Status in linux package in Ubuntu: Confirmed Bug description: I have a 4k dell monitor attached to a Dell XPS13 (2020). The connection is: Computer -> Thunderbolt (USBC) Cable -> Caldigit Thunderbolt Hub -> Thunderbolt-to-Displayport Cable -> Monitor. Note: The Thunderbolt cable from the Caldigit hub is powered. I have a keyboard, mouse, monitor etc all attached to the thunderbolt hub. So there is just one cable connected to the laptop, which is nice. If I wake my laptop, everything's fine for a few minutes, then periodically the screen goes black for a second or two, then back to display. This happens with increasing frequency. If I log out and log back in, the problem is usually resolved. Sometimes I have to unplug and replug the hub from my laptop. I assume this is xorg-related because logging out and back in effectively restarts X. But X might not be the problem, it might be thunderbolt-related. ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: xorg 1:7.7+19ubuntu14 ProcVersionSignature: Ubuntu 5.4.0-37.41-generic 5.4.41 Uname: Linux 5.4.0-37-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.2 Architecture: amd64 BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log' CasperMD5CheckResult: skip CompositorRunning: None CurrentDesktop: ubuntu:GNOME Date: Wed Jun 17 18:22:45 2020 DistUpgraded: 2020-04-28 11:49:08,077 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py' DistributionChannelDescriptor: # This is the distribution channel descriptor for the OEM CDs # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor canonical-oem-somerville-bionic-amd64-20190418-59+beaver-osp1+X00 DistroCodename: focal DistroVariant: ubuntu ExtraDebuggingInterest: Yes, if not too technical GraphicsCard: Intel Corporation Iris Plus Graphics G7 [8086:8a52] (rev 07) (prog-if 00 [VGA controller]) Subsystem: Dell Iris Plus Graphics G7 [1028:096d] InstallationDate: Installed on 2020-03-14 (95 days ago) InstallationMedia: Ubuntu 18.04 "Bionic" - Build amd64 LIVE Binary 20190418-12:10 MachineType: Dell Inc. XPS 13 9300 ProcEnviron: PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/zsh ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-37-generic root=UUID=15b70d1f-6d44-4cea-a1ad-10b0924bc69b ro quiet splash vt.handoff=7 SourcePackage: xorg Symptom: display UpgradeStatus: Upgraded to focal on 2020-04-28 (50 days ago) dmi.bios.date: 05/08/2020 dmi.bios.vendor: Dell Inc. dmi.bios.version: 1.0.11 dmi.board.name: 077Y9N dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 10 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr1.0.11:bd05/08/2020:svnDellInc.:pnXPS139300:pvr:rvnDellInc.:rn077Y9N:rvrA00:cvnDellInc.:ct10:cvr: dmi.product.family: XPS dmi.product.name: XPS 13 9300 dmi.product.sku: 096D dmi.sys.vendor: Dell Inc. version.compiz: compiz N/A version.libdrm2: libdrm2 2.4.101-2 version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.4-2ubuntu1 version.libgl1-mesa-glx: libgl1-mesa-glx 20.0.4-2ubuntu1 version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.1 version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1 version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1 version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1884001/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp