Unfortunately bolts are not the issue.They only hold the linkage into the bands, they do not hold the bands in place. It sounds like you have stretched or worn bands. Time to crack it in half and take a look inside. If the bands are lined well then they have stretched. If the lining is almost gone or gone, re-lining them may do the trick, but your drums may be scarred and need attention. Take some pics and post them. We will be able to tell you what's going on, but yes it needs opened up.
l like to buy stuff and no I don't do payments!