SysBeep([n],[delay])
SysBeep is OBSOLETE. Use
Snd instead.
Play n system beeps (default 1), separated by "delay" ticks
(default 0) between beeps. Each tick is 1/60.15 second. The
beeps are still distinguishable even when "delay" is zero.
Psychtoolbox/PsychObsolete/SysBeep.m