Cisco : 1721 / 2610 - Old T1 Wic Is Not Interacting To V2

I've got three Cisco 1721's and a 2610, two of the 1721's are 32f's, the other one is a bit older but is still the same model. The two Cisco 1721 32f's have 1-dsu-t1-v2 wics in them, and the older 1721 has a 1-dsu-t1 wic in it. Now no matter how i have configured it the old t1 wic will not talk to the v2 wic. I've tried putting the old wic into a 1721 32f and it doesn't work at all!

What i have working:

router DCE (1721 32f with v2 wic) can talk to router DTE (1721 32f with v2 wic) no problem with this configuration.

Router DCE:

-service-module t1 clock source internal
-service-module t1 data-coding normal

[ code].....

Router DTE:

-service-module t1 clock source line
-service-module t1 data-coding normal

[ code]....

Router OLD (1721 with v2 wic) can talk to router DTE (1721 32f with v2 wic) no problem with same config. What doesn't work: Any router with 1-dsu-t1 (old) wic to router DTE (1721 32f with v2 wic). again same configuration as before, so whats going on that i cant get this to work? Is the old t1 wic not compatible with the new t1 wic?