This recently completed Houston, TX wall mount installation also featured in-ceiling speakers and volume control.  The homeowners had a in-law coming to stay with them so they wanted to expand their current whole house audio system to include another room.  We installed two in-ceiling speakers and a volume control into the wall near the light switch.  We also installed a HDTV wall mount above the dresser.  Power is taken care of by a power relocation kit.  The HDMI cables are also ran through the wall from behind the HDTV wall mount to the Directv receiver below.