Soft Flow Dyeing Mystery

In Tubular knit dyeing machine - soft flow - yesterday a dyeing master showed me a fabric roll dyed in medium depth navy blue shade. They have used Dystar RGB type of dyestuffs. To my surprise, exactly 1/2 of the tube appears slightly yellower and the other side appeared to be redder and bluer, throughout the length of the piece. They asked me what would be reason for this type of peculiar behavior? I just gave some of my suggestions and I would like you to share your experience with me.

Since the fabric is a double jersey type of one, due to heaviness of the fabric there is a possibility of one side of it getting abraded against the stainless steel parts of the high pressure of the nozzle. I suggested them (a) to increase the size of the nozzle, if possible; (b) increase the quantity of lubricant they are adding; (c) avoid using caustic soda in the dye bath.

Note: The fabric is not a mercerized one and it is open air dried one and not dried in the relax dryer.

Please comment on this please.