My David loom’s shed is not quite right

My David loom’s shed is not quite right.  (I have the sliding beater).  My shuttle keeps catching warp threads when it glides along the shuttle race.  I tried changing the shuttle I am using so that now I am using a shuttle that has turned up ends.  This helps a little bit.  It seems to me that the warp threads should go to the bottom of the reed when the shed is open but the warp is actually about 1/4 to 1/2 inch above the race.  Since the beater height is not adjustable I am assuming I have to tweak the lam cords somewhere but I am not sure where and what to do.  Any suggestions?

The beater is adjustable.  There are two wooden blocks on the side of the loom.  They are attached with wing nuts.  All you have to do it loosen them off and move the blocks up and retighten.  Those blocks hold the gliding rods that the beater runs on.  Let me know how that goes.

OMG! I tried adjusting the wooden blocks on the side of the loom and problem solved!  Maybe I might have eventually figured that out myself but probably not as I am not mechanically talented.  Thank you so much!