AacCodecProfile
Specify the AAC profile. For the widest player compatibility and where higher bitrates are acceptable: Keep the default profile, LC (AAC-LC) For improved audio performance at lower bitrates: Choose HEV1 or HEV2. HEV1 (AAC-HE v1) adds spectral band replication to improve speech audio at low bitrates. HEV2 (AAC-HE v2) adds parametric stereo, which optimizes for encoding stereo audio at very low bitrates.