Every session, the PCs start out with rumors. Several of the PCs routinely get several each, and with the group size - 5 players is a smallish session these days - they get heard fast.
It's been very tough to get 30 rumors together, so the d30 has been retired. Even getting 20 has been tough - too many sessions retread mostly the same ground.
Since I assume a lot of rumors are sparked by people hearing about the previous sessions, plus a sprinkling of current events, this means less exploration / less encounters with something new = less rumors.
I may need to drop down to d12 if I can't keep up with new ones.
Another option is to go with one of the suggestions of a player - duplicate rumors are just that - duplicate. No cap on the number of rumors a PC can hear, everyone gets a unique rumor, but the ones with multiple rumors might just hear the same thing as other PCs.
We'd resolve the rolls for one-rumor folks first, and then let the guys who get two, three, even five or more roll.
And it's probably about time for Vic to get bored and re-read all of the rumors to see what they heard then and recognize now . . .