Designer Window "Reducing Colors" Message

Hi there, 

I'm with a print shop using DecoNetwork as a decoration app for our Shopify website. For some reason whenever I'm previewing one of our stock designs on a product in the Designer window I get the message "The system is reducing the number of colors in this design so it can be used by the selected decoration process." This happens regardless of the number of colors in the design, even solid white designs display this message. 

More confusing is that all of our designs are set for DTG as well as all of the products, so full color shouldn't be an issue. Any idea as to why this is happening and how to get rid of the message? It slows down the decoration process and is confusing to customers.