| PASS insertDTMF() should succeed if tones contains valid DTMF characters | |
| PASS insertDTMF() should throw InvalidCharacterError if tones contains invalid DTMF characters | |
| PASS insertDTMF() should throw InvalidStateError if transceiver is stopped | |
| PASS insertDTMF() should throw InvalidStateError if transceiver.currentDirection is recvonly | |
| PASS insertDTMF() should throw InvalidStateError if transceiver.currentDirection is inactive | |
| PASS insertDTMF() should set toneBuffer to provided tones normalized, with old tones overridden | |
| PASS insertDTMF() after remove and close should reject | |