I've been having a strange problem with Media Encoder CC 2014 & After Effects CC 2014. If I try to export a comp either through Media Encoder or directly from the After Effects Render Queue then it only exports audio. If I bring the AE Comp into Premiere and export from there either by sending it to Media Encoder or exporting it directly from Premiere then it exports fine and gives me audio and video.
Windows 7 64
i7 950 @ 3.07GHz
24GB Ram
Quadro 4000