Random Static Hits

What can I do to eliminate the random static hits that I'm getting with playing all of my vinyl. About 4 or 5 times a side, there's a medium loud pop right down the center. It doesn't happen in the same place if I play the LP again and it happen on every LP I've played in the last couple of weeks. The wall mounted turntable is a WT Simplex and it's grounded as always to a Herron VTPH-1MC. Nothing has changed in my system recently, but the weather has changed I guess.... it's dryer. Floors are hardwood so no spraying the carpet to increase humidity. Help!