"Sonic AS has 16 channels polyphony for the DS, and variable polyphony on the GBA." The application has been updated for both the GBA and NDS. Please see the project post for more information.
Change Log said:• DS runs with variable channel count (to allow stuff like libnds sound)
• GBA mixer code has been heavily optimized
• Music code has been revised
• Fixed pitch bend stuff
• Added SFX code