Nail pops were not real serious but they were there at different points interior of this brick. No ventilation of the space behind the brick, so that during the summer when it rained and was hot out, brick would soak up water, then due to moisture and temperature gradients, release it to the inside by diffusion when the air conditioning was on. home built in '84.
"Nail pops visible on the interior surfaces of walls with brick veneer appear to be the result of moisture migration. During the summer, when the home interior is cool and outside temperatures are high, moisture from rain absorbed by the porous brick may diffuse through the wall toward the interior, raising moisture levels in the drywall and causing bulging on the interior wall surfaces at drywall nail locations.
This appears to be part of a slow, long-term process and will probably continue. It is a cosmetic, rather than structural issue".