When having safety systems on. Dsd and aws. When you acknowledge the aws alarm, the alarm for the dsd goes off at the same time. You can even hear it when you randomly push the b button at anytime and the alarm for dsd goes off. Of course it goes off ever 30s or so i know, but i can push the b button during that time and the dsd noise plays. When i turn off dsd and acknowledge the aws it doesnt sound the dsd noise, only when i have the dsd activated it does it.