DVD Anomalies

I've found a number of DVDs already that have 5 channels (5.1 surround sound? offset of 1?) for the audio attributes of IFO zero.

Some of them include:

• Bon Voyage!
• The North Avenue Irregulars
• Matilda (PAL)
• A Bug's Life
• Disneyland, USA (both discs)

In comparison, every other DVD has zero or one channel. If there *is* an offset of one, then that would make them mono and stereo.