I've been curious lately which wifi channel my '14 rMBP 13" is using. I've set the Airport Time Capsule for Automatic 2.4GHz and 5GHz channels. How do I determine which channel I'm connected to? I'm located about 20 feet from the Airport but have it located behind my television. I'm also curious if that obstruction is keeping the rMBP from using the 5GHz channel.