HDMI TV resets exiting game

[DirtyScumbeast]

since installing the latest recalbox (pulsar) on Raspberry Pi 4 when exiting a game (hotkey & start) it sends a signal to my LCD TV to restart somehow. connected via HDMI,
it's not the end of the world but very strange & takes longer to get to the menu obviously.
Does this in the different cores i've tried (neo geo, mame, megadrive) so seems to not be the core but maybe emulation station or recalbox sending a signal to the tv.