I have two identical fragramatics shampoo vacs. They are the SAV-S. I recently ordered new shampoos hose assemblies - the complete ones. I changed out the first one and it worked just fine. I finally got around to changing out the second one today but cannot get it to work. It is feeding air back thru the product pump into the gallon jug of product. There are only two lines in the hose.....the air line and the product line. I thought maybe the air line was marked wrong so I switched them but the same problem....I thought the air and product lines were totally separate and did not meet anywhere at the brush head they go into a plastic block that has holes drilled to accept the air and product...I assume this is where the air and product would be mixed but some how it acts as a closed loop with air overpowering the product and coming back around. Any ideas on how to correct this short of dending the hose back to the company for a replacement?