Check for any warping
Warping can often be caused by humidity and temperature changes. To check to make sure that your drums aren’t warped you’ll need to loosen the drumhead by untightening all the lugs. Once the head is loose take a close look at the rim; it should sit evenly across the rim of the drum with no dents or warping. If you notice any of this, you may want to think about getting the head replaced for a better and more consistent playing sound. When retightening the drumhead make sure to evenly turn the lugs to ensure that all tension is evenly distributed across the surface. You’ll know when the drum is tight enough as you should be able to play a crisp, loud tone.