I filter. Leave a pin in the top and heat in the oven at 200F for 20 minutes. Allow to cool and use. If I have soreness, I place a vent pin back in and heat in the oven for 15 minutes at 200F.
The soreness is from the BA being a little high. I always use a little more BA to make sure I am sterile and I cook it down to get it to a tolerable amount.
Never had a single problem with any of my grandpappy's brew.