your doing better than most players! Here and there just every year or two when you think about it, you can clean the inside with a qtip....i've seen gunk build up and make shafts fit way tighter than they should and such.
what i and some others do with those types of wood threads, especially on an older cue that the threads are starting to wear some.
tape off the joint of the shaft with painters tape.....have a little acetone or nail polish remover handy as well
pour some CA (superglue....a thin version....the cheap junk from harbor freight will work perfect for this.) into the threaded hole (THIN CA.....NOT MEDIUM....NOT THICK....it must be water thin)
FILL the hole with the CA.......let it set in the hole for a few seconds 5 or 10 is good.....then just turn it over and let it all run/drip out......
hang the shaft vertically with joint down for 15 or 20 minutes.....and then you can put the shaft back on and test fit.....and redo accordingly, its nice if you also have a 3/8 x10 tap as well, you can build the treads back up very nicely like this without having to go into the cue.....somecues this is the only option for a repair (customer may not want to spend the money to plug, bore and retap for new threads. use the acetone to wipe any CA immideately from the face of the shaft.
if you have 3/8x10 and especially no local repair man then you can get a tap, superglue and acetone for under 60$...the tap will last you forever doing that...and could do a friend or twos for a few bucks and probably pay for your tap. (about 30-40 dollars give or take)