What ^ Jimi D. said. I've got a batch of "clear" I DIYed from 100mg nic. in PG and straight VG (mixed to my preferred nic%). I sometimes mix 50/50 of my unflavored with the factory juices to cut the intensity. Getting a good vape from any particular RDA has enough factors without adding "flavor muting" to the agenda. In fact, muting flavor by changing the dynamics of your build will most likely result in other unpleasant side effects.
All that said, the easiest way to mute flavor on a horizontal coil in an RDA is to push the coil down. If the airhole/airflow is hitting more of the top of the coil than dead center, it'll mute flavor for you. It can also increase sweetness tho.
If your coil is a little above center (to air hole), and more air is passing under the coil, this usually reduces sweetness but enhances the acidic flavors and may increase TH a bit.
Anyway, point being: play with coil height in relation to air hole for minor tweaks of flavor profile and intensity.
ADDIT: Oh! Am I still talking?
oops, well I did think of one more thing to add. General rule is the larger the chamber of your atomizer, the less flavor you'll get. So, stay away from small atties if you don' wanna taste nothin'.