Environment Noise Filtering -U: Yes Audio Sampling Rate -U: 8 kHz/16 kHz/32 kHz/44.1 kHz/48 kHz Audio Compression -U: G.711ulaw/G.711alaw/G.722.1/G.726/MP2L2/PCM/MP3/AAC-LC Audio Bit Rate -U: 64 Kbps (G.711ulaw/G.711ala...