Cant get the OMAP L138 audio example to work

Hi,
 
We are trying to run and debug the MCASP_AudioExampleProyect over a OMALL138 LCDK. We can compile it and debug it without a problem, nevertheless it doesnt work. When we run it step by step, we have noticed that the function mcaspAppCallback is never executed, and, as a consequence, the program gets stuck on the semaphores semR and semT. We have tried it with 2 different hardware (same model). Their serial numbers are 4113L138053 and 4113L138033

We are working on the following path \pdk_OMAPL138_1_01_00_02\packages\ti\drv\mcasp\example\c674x\Audio
Code Composer Studio, Version: 5.5.0.00077 

Could you please explain us which is the reason for this behaviour? We are testing it over a LCDK S/N 4113L 138053.

Thanks in advance.