rosegarden 16.06 plays only first note, locks up PC when trying to use HR timer

[Marc]

I don't know why, but I cannot remember Rosegarden ever to be working during the last ten years.

I load up some of the examples shipped with it, try to play it, the playback counter starts to wildly fluctuate back and forth around the time point 0. When I try to set the HP timer as timer source for the sequencer, the entire PC freezes. I tried this with regular linux-generic kernel on amd64, and low-latency stock kernels from Ubuntu 16.10. The only way to get the timer on the playback display going forward is to select a recording or playback device as a timer source. But even then only the first note gets played and nothing more. I even tried not having any devices connected to rosegarden, but the playback timer just kept fluctuating around 0.

[Marc (marc32111)]

Latest kernel working is http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.7.10/.

[Ted Felix (tedfelix)]

Upstream dev here.

There is a bug in the ALSA drivers that causes the playback problem you describe. Kernel bug 177571 is the one: https://bugzilla.kernel.org/show_bug.cgi?id=177571. That patch needs to be added to Ubuntu's kernel to fix this.

The relevant patch in the linux kernel 4.8.y tree:

http://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?h=linux-4.8.y&id=0f574c90d7476474d6b4e1d032e75cdf6c722fb3

Upstream bug report: https://sourceforge.net/p/rosegarden/bugs/1537/

Unrelated: The HR Timer issue is a long-standing mystery that upstream doesn't have time to address right now. Use the PCM timers instead if you need better resolution than the system timer.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1637917

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Aere Greenway (aere)]

I tested Rosegarden on Ubuntu, UbuntuGnome, Kubuntu, UbuntuMATE, Lubuntu, and UbuntuStudio.

In all cases, in attempting to play a MIDI sequence (Rosegarden '.rg' file), wherever I placed the playback-position, it would play only the notes at that position, and not advance any further.

It is as if the timer is not advancing.

I was able to play those same sequence files, when converted to a MIDI-file (.mid) and playing it using the MIDI Player/Recorder of the KeyMusician Keyboard, which uses the MIDI sequencer in Open Java 8.

[Ted Felix (tedfelix)]

Confirmed in Ubuntu 16.10 with kernel 4.8.0-30.

ted@teds-laptop:~$ uname -a
Linux teds-laptop 4.8.0-30-lowlatency #32-Ubuntu SMP PREEMPT Fri Dec 2 04:38:54 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

ted@teds-laptop:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.10
Release: 16.10
Codename: yakkety

[Ted Felix (tedfelix)]

I've switched this back to confirmed since upstream is aware of the issue and the exact patch to the kernel that is required to fix it has been provided in this bug report.

[penalvch (penalvch)]

Mark, given the upstream fix patch was merged into 4.9, and http://cdimage.ubuntu.com/daily-live/current/ was rebased to this, it wouldn't hurt to confirm that the latest Ubuntu fixes the issue.

[Ted Felix (tedfelix)]

Confirmed that 4.8.0-32-lowlatency fixes this issue. Thanks guys.

[penalvch (penalvch)]

Mark, this bug report is being closed due to Ted Felix's last comment https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1637917/comments/9 regarding this being fixed with an update.

However, if this is still reproducible on 4.8.0-32-* please feel free to reopen this report.

For future reference you can manage the status of your own bugs by clicking on the current status in the yellow line and then choosing a new status in the revealed drop down box. You can learn more about bug statuses at https://wiki.ubuntu.com/Bugs/Status. Thank you again for taking the time to report this bug and helping to make Ubuntu better. Please submit any future bugs you may find.