OK, so I went into the BIOS settings for the machine, and the only options for the video configuration is to set video switching to either dynamic or fixed. Dynamic (which was selected) allows the system to switch between the video card "on demand", while fixed (which is now selected) requires the OS or the user to manually switch between video cards.
After setting the video configuration to fixed, I booted into Ubuntu and retried the mpv test with your video. I noticed only one brief lag (too fast to even let me try doing top or dmesg). Here is the output from mpv, which shows only a single dropped frame (which would be unnoticable for most people watching a video): tracy@tracy-hp:/mnt/VM$ mpv bbb_sunflower_1080p_60fps_normal.mp4 Playing: bbb_sunflower_1080p_60fps_normal.mp4 (+) Video --vid=1 (*) (h264 1920x1080 60.000fps) (+) Audio --aid=1 --alang=und (*) (mp3 2ch 48000Hz) Audio --aid=2 --alang=und (*) (ac3 6ch 48000Hz) File tags: Artist: Blender Foundation 2008, Janus Bager Kristensen 2013 Comment: Creative Commons Attribution 3.0 - http://bbb3d.renderfarming.net Composer: Sacha Goedegebure Genre: Animation Title: Big Buck Bunny, Sunflower version AO: [pulse] 48000Hz stereo 2ch s16 Using hardware decoding (vaapi). VO: [opengl] 1920x1080 vaapi[nv12] AV: 00:10:34 / 00:10:34 (100%) A-V: 0.000 Dropped: 1 Exiting... (End of file) tracy@tracy-hp:/mnt/VM$ So, at this point, it looks like the dynamic switching was the basic problem. However, of interest to me is why this didn't present in earlier versions (I have run 16.04, 17.04, and 17.10 (Wayland), none of which exhibited this problem). So, given this, is there something specific that you want in the way of system information, or are we going to write this off to a (relatively minor) BIOS incompatibility with something introduced in 18.04? (I can live with the manual switching, at this point, if that's what it comes down to...) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gstreamer1.0 in Ubuntu. https://bugs.launchpad.net/bugs/1774915 Title: Video lag when using totem (audio does not lag) Status in gnome-shell package in Ubuntu: Incomplete Status in gstreamer1.0 package in Ubuntu: Incomplete Bug description: Advised to file a bug report after posting on "Call for testing: Video playback in 18.04". Running 18.04 LTS as fresh install (not upgraded from previous version - older version still installed in separate partition). Xorg session. System: HP Pavillion DV7 (lm726av) - Intel Core i7 2630 processor, integrated Intel video Playing any local video file (regardless of video format - flv, mp4, avi), the video will randomly lag in playback. Audio is not affected, it plays back correctly. Very occasional lags in browsers (Firefox and Chrome) on pages with a lot of active graphics (flash or HTML5). Browser lags significantly improved after installing synaptic driver for touchpad operation (I have no idea why this would affect video playback - I simply note that it happened). I can pick a random video on YouTube and watch it in Firefox or Chrome without lag (even full-screen). However, if I grab a local copy of the video (using, for instance, Clipgrab) and play it using Totem, I get lag. I was also advised to try using mpv - I still get lag in mpv, although not as pronounced. tracy@tracy-hp:~$ sudo apt-cache policy totem [sudo] password for tracy: totem: Installed: 3.26.0-0ubuntu6 Candidate: 3.26.0-0ubuntu6 Version table: *** 3.26.0-0ubuntu6 500 500 http://us.archive.ubuntu.com/ubuntu bionic/main amd64 Packages 100 /var/lib/dpkg/status I was also asked to include output of lspci -k - shown below: tracy@tracy-hp:~$ lspci -k 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) Subsystem: Hewlett-Packard Company 2nd Generation Core Processor Family DRAM Controller 00:01.0 PCI bridge: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port (rev 09) Kernel driver in use: pcieport Kernel modules: shpchp 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) Subsystem: Hewlett-Packard Company 2nd Generation Core Processor Family Integrated Graphics Controller Kernel driver in use: i915 Kernel modules: i915 00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family MEI Controller Kernel driver in use: mei_me Kernel modules: mei_me 00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family USB Enhanced Host Controller Kernel driver in use: ehci-pci 00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family High Definition Audio Controller Kernel driver in use: snd_hda_intel Kernel modules: snd_hda_intel 00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.1 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.2 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 3 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5) Kernel driver in use: pcieport Kernel modules: shpchp 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family USB Enhanced Host Controller Kernel driver in use: ehci-pci 00:1f.0 ISA bridge: Intel Corporation HM65 Express Chipset Family LPC Controller (rev 05) Subsystem: Hewlett-Packard Company HM65 Express Chipset Family LPC Controller Kernel driver in use: lpc_ich Kernel modules: lpc_ich 00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller (rev 05) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family 6 port Mobile SATA AHCI Controller Kernel driver in use: ahci Kernel modules: ahci 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05) Subsystem: Hewlett-Packard Company 6 Series/C200 Series Chipset Family SMBus Controller Kernel modules: i2c_i801 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Whistler [Radeon HD 6730M/6770M/7690M XT] (rev ff) Kernel driver in use: radeon Kernel modules: radeon 07:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06) Subsystem: Hewlett-Packard Company RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller Kernel driver in use: r8169 Kernel modules: r8169 0d:00.0 Network controller: Intel Corporation Centrino Wireless-N 1000 [Condor Peak] Subsystem: Intel Corporation Centrino Wireless-N 1000 BGN Kernel driver in use: iwlwifi Kernel modules: iwlwifi 13:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5209 PCI Express Card Reader (rev 01) Subsystem: Hewlett-Packard Company RTS5209 PCI Express Card Reader Kernel driver in use: rtsx_pci Kernel modules: rtsx_pci 19:00.0 USB controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 04) Subsystem: Hewlett-Packard Company uPD720200 USB 3.0 Host Controller Kernel driver in use: xhci_hcd You will note that the system has both the integrated Intel video and an ATI Radeon card installed - the system is using the integrated Intel video. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: libgstreamer1.0-0 1.14.0-1 ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17 Uname: Linux 4.15.0-22-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.1 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Sun Jun 3 22:52:48 2018 InstallationDate: Installed on 2018-05-09 (25 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: gstreamer1.0 UpgradeStatus: No upgrade log present (probably fresh install) XorgLog: Error: [Errno 2] No such file or directory: '/var/log/Xorg.0.log' To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1774915/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp