Recordings that are less than 3 seconds cannot be transcribed. Twilio uses an automated transcription system that is unable to recognize and process short recording files. Any recordings less than 3 seconds that are transcribed will be noted as "(blank)".
Legal implications of call recording
If you choose to record calls, you need to comply with certain laws and regulations, including those regarding obtaining consent to record (such as California’s Invasion of Privacy Act and similar laws in other jurisdictions). Additional information on the legal implications of call recording can be found here.
Notice: Twilio recommends that you consult with your legal counsel to make sure that you are complying with all applicable laws in connection with communications you record or store using Twilio.