Susan,
I have seen many clicking babies, it seems to me that they are losing tongue
contact with the breast, which is what makes that clicking sound.  Several
causes: short lingual frenulum that causes a rebound snap when the tongue
attempts to extend and elevate to press milk from the breast (that short
tongue and inability to get the tongue over the gumline?); weak jaw (tongue
and jaw movements are linked, especially in young babies, when the jaw opens
excessively during suckling, the tongue is pulled away from the breast); or on
purpose to reduce the effectiveness of suckling when the mom had an overactive
MER.
        First be sure that there is no adaptive reason that the baby is doing
this.  Babies often find interesting solutions to feeding problems.  Removing
the solution without going after the cause might make things worse.
        For a short frenulum, the mom might want to consider evaluation by a
breastfeeding friendly family doc, ENT or pediatric surgeon.  If she will not
consider frenotomy ( a little snip with a sterile scissor under topical
anesthesia), I have found nursing in a football hold where the mom leans back
and the baby's face is approaching the breast tongue first helps.  The more
open she can get the mouth, the less a short frenulum hurts the mom.  If baby
does not respond to tapping the lip, have the mom brush it very very VERY
gently with her nipple.  Paradoxically, babies often respond better to a
gentler stimulus.  If this is the problem, it is very fortunate that the mom
has looser breast skin,  if she were a playboy centerfold, nursing a baby with
a short frenulum would be torture.
        If the problem is a weak jaw or low muscle tone in the face, the
dancer hand position is helpful.  Making sure the baby is positioned in
perfect alignment and well supported is vital for any type of sucking problem.
 Stability and function go hand in hand...
        If the mom has an overactive MER (which I suspect is often
compensatory for a baby's poor suck) have her try to nurse frequently, one
breast only per feeding, feed when baby is a bit sleepy, or try feeding
standing up or walking around.  The Avery LC series module on this topic is
excellent.
        I'd be interested to know if any of this is helpful, and what your
further observations of this baby are.
Catherine Watson Genna, IBCLC