mice and keyboards stop working if enabled as HID controllers

[mixxxbot]

Reported by: olarncpn
Date: 2021-08-20T02:32:54Z
Status: Fix Released
Importance: Undecided
Launchpad Issue: lp1940599
Tags: mouse, usb
Attachments: [gdb output](https://bugs.launchpad.net/bugs/1940599/+attachment/5519236/+files/gdb output)

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Laptop: Aspire-E5-572G
CPU:Intel i7-4712MQ
OS: Linux Mint 20.2 kernel version 5.4.0-81-generic
MIXXX: 2.3.0
Mouse: Wireless Logitech

When start MIXXX, mouse and touchpad stop working. I have to resetusb to recover.
Or otherwise I have to unplug mouse and plug it again.

[mixxxbot]

Commented by: olarncpn
Date: 2021-08-20T02:32:54Z
Attachments: [gdb output](https://bugs.launchpad.net/mixxx/+bug/1940599/+attachment/5519236/+files/gdb output)

[mixxxbot]

Commented by: Be-ing
Date: 2021-08-20T02:46:19Z

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That is a very curious backtrace...

[mixxxbot]

Commented by: Be-ing
Date: 2021-08-20T02:46:34Z

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What version of Qt are you using?

[mixxxbot]

Commented by: rah2501
Date: 2021-08-22T10:47:51Z

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I have the same behaviour. Intermittently but more often than not, both mouse and keyboard are grabbed by Mixxx and freeze on startup. I have to disconnect and reconnect my KVM to get back control of the desktop.

This is on Debian Bullseye with both 2.2.4 and 2.3.0.

[mixxxbot]

Commented by: Holzhaus
Date: 2021-08-22T12:25:15Z

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Are these HID devices and enabled in the controllers panel? I noticed that my keyboard is shown as a controller and if I enable it, it stops working while Mixxx is running.

[mixxxbot]

Commented by: olarncpn
Date: 2021-08-24T01:31:13Z

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Thank you for your response.

Q:[Be: What version of Qt are you using?]
A:Qt 5.12.8 .

Q:[Jan Holthuis (holthuis-jan) Are these HID devices and enabled in the controllers panel? I noticed that my keyboard is shown as a controller and if I enable it, it stops working while Mixxx is running.]
A:I am using Linux Mint which have not many menus to setup keyboard or mouse. Would you please guide me which command or which "system setting" menu should I look at to set the "HID devices enable/disable".

[mixxxbot]

Commented by: Be-ing
Date: 2021-08-24T17:12:42Z

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Jan was referring the Controllers section of the Mixxx preferences, not any system settings.

[mixxxbot]

Commented by: olarncpn
Date: 2021-08-25T01:26:54Z

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That's the catch!!

I disabled all controllers displayed in preferences-->Controllers. Then mouse and touch pad not freeze after start MIXXX ..

-BUT-

Those settings not lasting long. I disabled them once --> press Apply --> OK, and after restart MIXXX, those settings set to enabled again. And mouse pointer freeze after MIXXX start at the second time.

Anyway, this is the "setting" which interferes mouse behavior, for sure.

I work around by, set "Load Mapping" to "Not preset" press --> OK and exit MIXXX. Those settings are not back to Enabled (dimmed to gray color). And I do not get the freeze mouse after start MIXXX anymore.

Is this still a BUG?

Thank you all for your help.

[mixxxbot]

Commented by: Be-ing
Date: 2021-08-25T05:40:09Z

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I opened a pull request to hide mice and keyboards from the list of HID controllers so no one else gets confused by this:
#4243

[mixxxbot]

Commented by: daschuer
Date: 2021-08-25T06:07:28Z

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I disabled them once --> press Apply --> OK, and after restart MIXXX, those settings set to enabled again.

Do we have a clue why this happens? This seems to be the root cause of this bug that should be fixed. I remember a project where user uses a second mouse for scratching. Not sure If that's still the case.

[mixxxbot]

Commented by: Be-ing
Date: 2021-08-25T06:33:10Z

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I disabled them once --> press Apply --> OK, and after restart MIXXX, those settings set to enabled again.

This is another bug. It is an issue of the preferences GUI getting into a confusing state. The controller is not actually enabled after disabling it and restarting Mixxx, but the Enabled checkbox is checked in the preferences, so it is easy to accidentally re-enable it. I have opened a separate bug for this: https://bugs.launchpad.net/mixxx/+bug/1941042

[mixxxbot]

Issue closed with status Fix Released.