About the KS34465A: mine is on the latest FW, and also by hand testing, it is unusably slow. Maybe I got a hidden (read: SCPI) setting wrong. Found nothing related on the KS itself: one can only set beep on/off, no thresholds, nothing. Maybe another owner can confirm?
But hey, this topic is getting out of hand, it is supposed to be about the SDM4000A. And I'm partly guilty. This beep thing is more a subject for the DMM excel sheet.