65L bought summer of 2019. Modifications include pulling the overflow pipe and plugging the mash pipe with a stainless steel plug.
1. I wet condition the grain before milling. Even before I was wet conditioning I didn't have any issues with recirculating though, the conditioning helps with the muck and dust. Right now I'm milling at .34.
2. I mash thin 2 qts/pound of grain. So for a standard 1.050 beer I'm mashing in with 11 gallons.
3. I mix the grain in for the mash adding rice hulls as I go...three handfuls total. I mix everything well let it rest for 10 minutes then start recirculating with this:
Eagle Brewing BE510 Siphon Spray Wort Aerator https://www.amazon.com/dp/B00ODSS5J8/ref=cm_sw_r_cp_apip_pUnZs1AJRsAE2
I use the Hochkurz mash steps. First step at 144° for 30-45 minutes. Stop recirculating, mix really well let it rest 10 minutes and then recirculate and bump temperature up to 158 for 30-45 minutes.
Once done I pull the pipe, sparge with my Digiboil 1/2 gallon at a time...sometimes i put the top screen on sometimes I don't.
Never had a stuck sparge using this method. What it sounds like to me is your mash is too compact or channelling is happening interupting the flow of wort from top to bottom.