Everybody gave good tips (clean the hookah & hose, try a different brand, take a break), but also try adding alittle cold water to your base (after the break -
}, see if that helps. I often find if the taste is weak, cold water in the base helps bring out the taste more (but don't go too overboard on the "cold" thing - too much can kill all the flavor).
If none of these help.... I'm at a loss... maybe make a vid and post it, that way we can all see how you set-up & smoke and maybe offer more help.