Michael says “setting 5 = pretty minimal, setting 4 = -5db, setting 3 = -10db, setting 2 = -20db, setting 1 = -35db”
180125 manual says “Output Attenuation Amount: Six Steps (dB): 0, 6, 12, 24, 36, ∞ (speaker off)”
180220 manual says “Output Attenuation: Five Attenuation Steps and Speaker Off”