Spotted in X1C Machine Start G-Code:
;===== machine: X1 ====================
;===== date: 20240919 ==================
;===== start printer sound ================
M17
M400 S1
M1006 S1
M1006 A0 B10 L100 C37 D10 M60 E37 F10 N60
M1006 A0 B10 L100 C41 D10 M60 E41 F10 N60
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