 SVCDs may have two separate stereo, or four mono audio tracks (for commentary or additional languages).Audio may have up to 6 channels (in a 5.1 arrangement) using the MPEG Multichannel surround sound format, although space constraints and inconsistent hardware support make it impractical, and very uncommon.Variable bit rate encoding, while not supported by the MPEG-1 Audio Layer II standard, is part of the SVCD specification.