How much is she getting in 24 hours? She needs a minimum of 20oz of milk, that can include milk in foods but, you are right that milk should be her main source of nutrition for a while yet. Have you tried cutting solids back slightly to see if that increases her milk intake? Are her milk feeds before her solids feeds?
Have you tried a faster flow teat? Teething could well be to blame too, teething gel just before a feed may help. You could start weaning the DF, it's usually around 7/8 months when they are more established on solids that it can be dropped.
If you like, post your EASY putting in milk/solids times with the amounts she has for us to have a look at!
Laura