I seem to see signs of new growth so I am going to guess the brown is winter damage and can be clipped out and then the new growth will cover the cuts. Do they get enough water? I note they are close to the house and sometimes this means the eaves are preventing rain water from getting to the roots. Do not let the foliage get constantly wet from a sprinkler as this encourages a leaf blight. There is also a boxwood blight disease and if the shrubs continue to fade I would give them the shovel solution (dig them out) and replace with more blight resistant Japanese holly. Keep growing, Marianne Binetti