When I'm looking to build muscle, I drop most cardio routines and focus on weight lifting. I have a very fast metabolism, and the amount of calories I'd need to both build muscle and keep up with running was just not going to happen.

So my advice? Probably add one or two more lifting sessions a week, increase your calories and protein, and drop cardio as much as you can. Once you've gained some muscle, bring your calories back down and go hard on cardio to get rid of any fat that came with the muscle mass.

Also, cardio (especially something as hard on your body as running) can impede muscle recovery in between lifting sessions. To build muscle, each week you want to be able to increase the weight that you're lifting by 5-10% (or increase your reps). If you find that this isn't happening, it's likely you're not letting your muscle recover enough between workouts and the effort you're putting them through isn't enough to trigger muscle growth. So say you take a break from running and lifting for a week. Then, the next time you do a set of squats you find you can do 15-20% more weight than your previous workout--that's a sign that before you were doing squats with fatigued muscles, which is going to impede both strength and muscle building.

There is a lot to be said about balancing running and weight lifting, but imo unless you consider yourself an athlete, or have professional guidance, I'd focus on one or the other.