Learn to make a breath attack? That is, don't rely on the tongue to start the note. Use a gentle "puff" of air to start the note. Practice over and over using smaller and smaller "puffs". Repeat ad nauseum; in fact, run 1/2 note scales without using the tongue but making sure that there is silence before starting the next (don't slur). When you've got that, go for 1/4 notes..... and so on. When you have a reliable breath attack and the note starts EVERY TIME, then you'll find that you won't be obsessing over the tongue attack.