For others of us we have no problem listening, but cannot decide who or what to listen to.

There are many different ways to go about choosing listening assignments.  For a snare or tenor line it is generally good to be listening in to the center, or when marching in a vertical line, you must listen back to the person farthest backfield.  You must listen back in this situation because if you listen forward, your sound will be late.

There is also the business of having the battery play to a metronome.  When Dr. Beat is on, Dr. Beat is God but take this comment with a grain of salt.  In this situation, the center snare and tenor are trying to lock in with the met so the others can clean to them.  If you are a wing, still try to listen to the met, but if the centers are doing a horrible job of keeping to the met, just follow them.  It is the center's job to keep consistent and with the met. 

Its really pushing me to even say anything like this, but a clean sound that is not with the met is better than dirt.  It is good to be striving for perfect timing, and it is everyones job to contribute, but the centers are truly the root of a line's timing.  That is why it is important to have the most consistent players as centers.  The rule is, don't make the center clean to the rest of the line.  You must clean to the center.  That gives you the best chance of having the right timing. 

So if the centers are dirting hardcore when a metronome is on, if their head is screwed on straight that day, its because they're trying to listen to the met.  Listen, make a judgement on which it is and follow.   

Bassline listening assignments are a little different.  There are none, until you get really good.  Each member of the bassline must be the ruler of their own beats and must be masters of time.  Members of the bassline must be able to do things like divide their quarter notes into equal pieces and play fragments of triplets.  The only real listening you should be doing right now, is the listening that's making sure you're almost treading on the person before your's split parts, but that isn't really listening, that's just timing.  So actually... the only real listening you should be doing is listening to a met.