I had another play with my zynth yesterday. From a fresh boot I set up 3 layers:
1 - Linuxsampler with SalamanderGrand loaded
2 - Pianoteq (“full” demo version, not the LV2) - edit: I’m using version 6 of Pianoteq as included in the standard Zynthian SD image.
3 - Linuxsampler with trombone loaded
This was all working OK and I was able to switch between the 3 layers multiple times and get the correct sounds play with midi input. After approx 10 mins layer 3 stopped producing sound when I went to change the trombone to a cello sound. I could still get layer 2 with pianoteq loaded to produce sound, and change between different piano presets. Layer 1 with Linuxsampler/SalamanderGrand continued to produce sounds, but I was no longer able to change to a different instrument sound. The Zynth interface was behaving normally and made it look like had changed to a different instrument sound, but the audio produced was still the SalamanderGrand patch.
From memory, the problem seems to be triggered when the instrument is changed, and doesn’t appear to exclusively affect Pianoteq. Could it be an issue with reading from the SD card?
@riban you mentioned log files… where might I find/extract log files?