Suspend/wake with HDMI external monitor causing shell crashing/reboot

All “Menu > General” settings are as follows:

Language - English
Smart Energy Savings - Off
Power LED - Off
Automatic Standby - Off
HDMI Compatibility Mode - greyed out
DisplayPort version - greyed out
Variable Backlight - greyed out
Buzzer - Off (not sure what this is?!)
OSD Lock - Off
Information - uptime/resolution info