I decided to throw caution to the wind tonight and cracked open my DX1, blatently ignoring the warning sticker on the back of the DX1 that reads “Under no circumstances should this label be removed. … Tampering with or removing this label will nullify all product warranties and will likely cause your DX1 Input System to malfunction”. I'm happy to report that my DX1 is still functioning perfectly after this procedure. The label itself is metal backed so probably does serve some purpose, personally I cut a slit into my label around the center hole (under which is a screw that needs to be removed before the unit can be opened) so that I could fold the label back down again.
Here's the numbers from the IC's on the main PCB:
SILABS F321 DCNA92 0521+
Programmable Micro-controller
The Silicon Laboratories, Inc. C8051F321 is a High-speed 8051 MCU with 21 I/O Lines, 25 MIPS Throughput, 25MHz System Clock, In-system Pogrammable, 4 Timer/Counters, Real-time Clock, PCA, Compare/Capture, 10-bit A/D Converter, SMBus, I2C, SPI, UART, USB, 1K Byte USB FIFO, 16K Bytes FLASH, 256 Bytes Data, 1K Bytes XRAM.
72C B407
P435B MM74HCT 164M
MM74HCT164 8-Bit Serial-in/Parallel-out Shift Register
Fairchild Semiconductor product page
P14SF 74AC00
74AC00SC Quad 2-Input NAND Gate