I have experienced this recently: a player raised 100 over a 60 bet made by another player, but upon doing so, put the 100 chip at the bottom of the 6x10s comprising the initial bet and just barely tilted them over. This caused another player, who indeed was listening to music and did not hear the dealer say 160 raise, to call the initial 60, binding him to also call the 100. After suggesting to the dealer that, perhaps, he should have split the raise into the 60 stack and the 100 next to it, to be more visible, the guy blasted off and I got into an altercation with him and the floor manager, who took the dealers side.
Was I wrong?