Menstrual Cup TMI

I've been using a cup for about 6 months now and I really prefer it over tampons.  However, just in the past couple months, it's been starting to SMELL by the second or third day of my period.  I only notice it when I take it out to dump it, but wow, it's potent.  I know this is TMI, but does anyone else have this problem?? I'm beginning to not want to even use it anymore because this never happened with tampons 😖😖
 P.S.  I soak it in hydrogen peroxide after each period, so it's not a smell from like buildup over the months. 
PPS.  I don't have a smelly vagina any other time than this 😫 Help y'all!