Whats that sound with Volume set to off?


I have two turntables, Using the same cartridge and tracking force with volume off, I can really hear the music from the record while the other turntable the cartridge is relatively silent.  Why?
tzh21y
I wonder if it is the record vibrating.  Do the two tables have different record clamping systems or platter mats?
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its just something I noticed and never gave thought to. i never knew it could be so different. one table is a VPi Aries with a screwdown clamp clamp, the other is a technics 1200g, no clamp. The 1200G is the quiet one.