How often do you clean it out? How many chickens do you have and what volume of pine shaving are you talking about. Do you use a droppings board to remove some poop from the mix or maybe to add pure poop to the mix? How often do you add fresh shavings? In other words, it depends.
The idea of the deep litter method is that your coop become the compost pile. You keep it moist enough that the microbes that break it down can live and multiply but not wet enough to smell, go sour, and become unhealthy. I'm not sure you are doing that or if you are, how long you leave it to work.
The closer you are to the ideal green:brown ratio the faster it will compost, assuming you keep the moisture levels in the right range. How often you turn it makes a difference. But even if the green:brown ratio is off quite a bit it will still break down eventually. Too much brown is usually better than too much green, if it has too much poop in it then you can attract flies or it will hold enough moisture to stink. So if it starts to stink or attracting flies, add some browns and turn it.
I also use wood shavings as litter in the coop but I don't do the deep litter method. My coop is too dry for it to break down. Once every three or four years I clean it out in the fall and put that on my garden, then till it it. By planting time it has broken down. Many people clean it out every year in the fall and spread it in the garden. I should but am too lazy. Some people clean their coop every six months, some as often as each week. Some people compost that, some send it to the land fill. Some make their run into a compost pile and just dump it in there.
I use a droppings board to catch pure poop. In my compost pile I put garden wastes, grass clippings, kitchen wastes, and the pure poop from the droppings boards. I usually only turn it once. I should turn it more but as I said I'm lazy. Twice a year I sift that through a frame I made out of 1/2" hardware cloth. Anything that goes through is compost, everything else gets tossed into the new compost pile to keep working.
We all do this differently. It doesn't have to be that hard. Just for fun I'll give this link. It was made by Master Gardeners when I was in Arkansas.
Compost Happens