Fixed track change bug with radio type E. Fixed audible resume bug. Fixed minor letter seek bug. Supports AAC decoder
Above is the extent of the changelog from 6 to 7, and the HU support listed is identical. Is there anything in there you actually need from version 7? I do have an Audi box but it would be a pain to trade and I don't understand how those minor changes could require new hardware. What does it DO with firmware version 7 loaded? Can you get a logfile of it trying to run?