generate questions: Encoder / decoder overall delay is not defined, which means there is no official provision for gapless playback. However, some encoders such as LAME can attach additional metadata that will allow players that can handle it to deliver seamless playback.
What is there no official provision for? {sep_token} What is an example of an encoder that can attach additional metadeta? {sep_token} Adding additional metadata allows players to handle gapless playback and deliver what? {sep_token} For encoders and decoders, what is not defined?