FX parameters reset after "OK" in preferences

[OsZ]

`effects.xml` should always store FX parameters until I change them inside the GUI. That unfortunately never worked for me. Was long time on KDE neon, then interim on Manjaro and now running EndeavourOS. Always the same issue, FX are reset to default parameter settings randomly, e.g. when closing Mixxx and start it up again. If several items are changed in the preferences window then this bug can be reproduced. I tried with changing sound output, change Live stream from one to another and even changing the default color for the Hot Cue resets FX parameters when pressing `OK` in the preferences window. It does not reset when pressing `Apply` though.

Depending on the FX used this can lead to disturbed or no sound during a Mixxx session (e.g. the moog filter defaults to LPF=0 that results in no sound at all)

Solution:
- Keep FX parameters unaffected by other changes in Mixxx
- set all parameters to default values that DO NOT change / transform sound

I tried with 2.3.0-beta (build makepkg r8110) & latest Beta (downloaded Apr, 7th).

Bug #1795661 was similar but closed without solution

PR #2618 seems to resolve the issue but is targeted towards Mixxx 2.4. When trying the PR #2618 I only checked for updates inside the Preferences window but not long term about FX parameters reset over sessions periodically.

This should be treated as critical bug because it can harm a live session if one must change a setting in preferences while playing.

Edit: The log file doesn't show anything about this behavior.

[OsZ (toszlanyi)]

Bug #1803580 seems similar. In there is a solution to avoid changes of FX parameters when preferences are changed.

-> In Preference window press `Apply` and `Esc` instead of `OK`.

To solve the periodically occurrence when restart Mixxx you can setup your FX parameters and then copy `effets.xml` to a separate file, e.g. `effects.default`. Now start Mixxx with a little bash script that copies the default settings first to the original file before launching Mixxx.

for Linux based OS this could look like:

#!/bin/bash
cp ~/.mixxx/effects.default ~/.mixxx/effects.xml
mixxx

[Daniel Schürmann (daschuer)]

I can confirm this with the current 2.3 beta

[ronso0 (ronso0)]

Is this reproducible with Mixxx' built-in effects only or with external LV2 effects involved?

[Daniel Schürmann (daschuer)]

I can confirm this with internal effects only.

[ronso0 (ronso0)]

shold be fixed by https://github.com/mixxxdj/mixxx/pull/2618
https://github.com/mixxxdj/mixxx/pull/4467 respectively

PLease re-open if you can still reproduce it.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/10388