Flash the ISD sound chip of Xbox 360 sim consoles in software. No soldering required!
Use the J-Runner ISD sound editor to create a .bin file. Guide
Place the .bin on the root of a fat32 drive as "isdflash.bin"
Follow the on screen text.
View the scripts subdirectory.
If the ISD is non responsive, unplug the 360, wait a bit then plug it back in.
For streaming audio data to the ISD (yes, you can do that) view README-spi for info
View notes.txt for information about the bitrate and compression header of Voice Prompt audio data.
Main ISD library from Balázs Triszka's PicoFlasher