Hi Sylvain,

Resent it to the list as requested.

I tried to use the 'gr3.7-qt5' branch today, and after successful compilation, I am getting this error message on the terminal:

[+] Available device: 0:0 <NVIDIA Corporation> NVS 4200M
[+] Selected device: NVS 4200M
[!] CL Error (-59, /root/gr-fosphor/gr-fosphor/lib/fosphor/cl.c:438): Unable to queue clear of spectrum buffer

I attached the complete output of the event, if you want to take a look. I also attached the screen how it looks during the run.

OpenCL works fine otherwise, and I used gr-fosphor successfully on this same machine before. I am on Ubuntu 18.04.03 LTS with the proprietary Nvidia driver (v390). The gnuradio is 3.7.13.5 (comes with the ubuntu repo, not compiled from source).

If you have any idea, or you need more info, debug log etc. please let me know.