There is an audio mixer bit in the VoiceProfile entry. For information about setting the audio mixer bit in the VoiceProfile entry, see Creating a VoiceProfile INF File Entry.
The following entries in SmpVoice.inf describe the audio mixer used by the voice modem:
HKR,, VoiceMixerMid, 1, 02,00
HKR,, VoiceMixerPid, 1, 99,01
HKR,, VoiceMixerLineID, 1, 00, 05 00, 00
For more information about these INF file entries, see VoiceMixerMid.