13232: Dial->Conference: Invalid startConferenceOnEnter value

Twilio returns this warning when the <Conference> noun inside <Dial> includes a startConferenceOnEnter value other than true or false. Use startConferenceOnEnter to control whether a participant starts the conference when joining. If you omit the attribute, the default value is true. If you set it to false before the conference starts, that participant is muted and hears background music until another participant joins with startConferenceOnEnter="true".

• The <Conference> noun sets startConferenceOnEnter to a value other than true or false.
• A dynamic value in your TwiML or application logic resolves to an unsupported value for startConferenceOnEnter. The attribute only accepts true or false.
• You are trying to implement a moderated conference, but the participant who should start the conference was not assigned a valid startConferenceOnEnter value.

• Set startConferenceOnEnter to true or false in your <Conference> TwiML.
• Remove the startConferenceOnEnter attribute if you want to use the default behavior. The default value is true.
• If you are building a moderated conference, set startConferenceOnEnter="true" for participants who should start the conference and startConferenceOnEnter="false" for participants who should wait in the lobby with background music.
• Validate the value before you generate TwiML so your application only sends supported boolean values.

• <Conference> TwiML noun
• <Dial> TwiML verb
• Conferences Participants subresource