K3b (and Brasero) DVD burning problem

I have a problem burning DVD discs on Manjaro. Tried k3b and Brasero and they act the same. Tried to burn mp3 files to a DVD disc. Used maximum speed - 16x reported in both apps. Somewhere around 50% of a burning process speed just drops to 0 and then settles at 4x. Burning finishes, both apps say successfully, no errors, but disks are not readable anymore. Files cant be copied back to pc, disks are corrupted. I have a k3b log file: k3b log.