The Archos PMA400 is a cross over between a Portable Media Player and a Personal Digital Assistant. It features a custom chip by Texas Instruments that combines an OMAP1510 and a DM270 on one chip. Both CPUs are double core CPUs with an ARM core and a DSP-core each making the PMA have four processing cores. Only one of the cores is accessible for execution of standard programs, the others are reserved for the multimedia functionality (video decoding, video encoding, audio) and can only be accessed via a library provided by Archos.
OMAP5910 Main Processor
TMS320DM270 Video Chipset (seems to be used for DSP video encoding/decoding)