POS Using Wrong GL Sales Account

When using POS the GL Sales Account for line items may be set up to use the default sales account for the customer. If you would like to use the sales account specified for items, you'll need to do the following:

Go to Admin -> Inventory -> General Setup. 

Check the option Use ITEM Sales Account (Not Customer) and click Save. After doing this the GL Sales Account for line items will be the sales account assigned to the selected inventory item.