in recalbox.conf
## Dreamcast emulator ## Like N64, such a CPU intensive emulator needs a small resolution ## Consider DMT 4 HDMI or DMT 9 HDMI. Mode 9 is selected for a better screen compatibility dreamcast.videomode=DMT 9 HDMIChange from DMT 9 HDMI to DMT 4 HDMI
I went through this situation, and there is everything here: https://forum.recalbox.com/topic/6453/4-1-unstable-bug-reports/282