P4VMM2 v1.x maximum CPU and HDD supported information as below,
HDD: 250G
CPU: Pentium 4 400Mhz FSB (256K/512K L2 cache) CPU – 2.6G.
          Celeron 400Mhz FSB (128K L2 cache) CPU – 2.6G

1. Audio pin definition:
P4VMM2 PCB V1.1 audio connector pin definition is not needed to short pin 5-6 and 9-10.
P4VMM2 PCB V1.2 and V1.3 audio connector pin definition is needed to short pin 5-6 and 9-10.
We suggest you need to check your front audio cable with your supplier about which kind of pin definition suits our P4VMM2 boards. And according to RD's information, this modification already phase in over 3 month. we think in your warehouse you should have two version of P4VMM2 in hand please help to check it out for these front USB/Audio cable issues. 2 / 4 - 4 / 11 : 18500pcs for P4VMM2 V1.1A4 / 14 : 3000pcs for P4VMM2 V1.32. Front USB header: for this board RD don't change the front USB pin define, always Intel pin define.

The P4VMM2 PCB: 1.3 only support P4 CPU 400MHz FSB feature.

No, the P4VMM2 v1.3 only supports to DDR266 maximum.