Well to be honest I too have tinnitus 24/7 non-stop, both ears constant same tone. The music and voices come over that. I also wear hearing aides too. Even with them off I hear the music and voices and noises. That's actually a advantage when I have my hearing aides off. Without them I have about a 50% loss of hearing. So with them off if I hear voices or music or noises, I know for sure it's me. At work I have to wear my hearing aides and it's not so clear as to what I am hearing. I do not grind teeth. There is no pattern for me. I can hear them any time under any mood. Some times for hours non-stop. Then they stop.
Last nite on my drive home I heard a voice repeat "justify or die" over and over again for about 15 minutes then stop. I don't consider this a serious problem as most of the time I can not make out what is being said as if people are talking from a distance, I can usually make out a word or two in those instances. Other times the voices are louder and very clear. The music is not bad unless it is non-stop for hours. It has not really effected my life except at work when I am not sure if some one is talking to me or not. I was just curious how common this was with folks with bipolar because I am wondering if I have SZA? I can't really say it only happens when I am manic or depressed, because it happens when I am baseline too.