Anyone have issue(s) with the double barrel extension for sprayers and APC's?

[cleanmycorolla]

Hey all! I have used a double barrel extension for waterless washes for a while now attached to my pressure sprayers, (this Double Barrel Extension Sprayer, sprayer extension wand, rotating extension sprayer), recently though, it seems an APC mix I used(Backfire APC 1:1) has clogged a barrel, it looks like soapy type residue. First any ideas how to unclog it? Ive tried pressured air, pin heads, everything....its driving me mental. 2nd, anyone have issues with strong APC mixes with it? 3rd, maybe it just went dead finally after all these years....

thanks in advance