Q Light Controller+

I maintainer of an installation:
P1 (controls) - P2 and P3 (QLCPlus 4.8.5 - standard images )
The installation runs now for several weeks, the PIs and network runs stable.
Unfortunately we have still the problem that QLCPlus crashes occasionally (on both P2 and P3)
As a workaround I wrote a "watchdog" which checks P2 and P3 and restarts them if necessary.
As it crashes to often and the malfunction is to obvious for the user, I'm under pressure to find the cause of the failures.

other "errors" (without crash):
"alsa under-run" (many messages) (didn't seem to have direct correlation to crash)
"Sound stops before light show has finished" (open issue)
P2 and P3 have the identical show files, P3 has no sound device (didn't seem to be a problem)

What we already tried:
we simplified the .qxw file
wav (instead of mp3)

if somebody has some ideas and hints for troubleshooting I would be grateful (meanwhile I'm going to the place).

many thanks in advance
Patrrick

I don't have Raspberry Pi, but anyway:

Can you do "ulimit -c unlimited" so that crashdumps are created?
I'm not sure where to put that, but quick google search will answer that.

If successful, "core" file will be created in current directory after crash.
This file contains exact contents of the program's memory and various useful informartion can be extracted from it,
like source line of the crash, content of local variables etc.

So, please:
- set ulimit,
- start qlcplus from a directory that you can write to and that has enough free space (~ equal to memory used by qlcplus process)
- reproduce the crash
- make sure/find the core file
- compress it and send to massimo (since I don't have the 4.8.5 rpi image). If running QLC+ program contains any private information like passwords etc. (e.g. in a script function) do not post it to public sites!
- send the exact RPi image version

thanks a lot for the debugging hint!
I will give feedback later, thanks
Patrick