Thanks everyone.
Here what i have done:
- reseated the CPU : nothing changed.
- reseated all the 5 RSTU : nothing changed
- tried a BSTU from another system : nothing changed
...but I did not test the RSTU in the other system. >:-(
Another thing, since the A/C failure, sometime my system loses its connection with the two other CIX670 and the PRI.
I do not know if this can be related?
My provider tested the PRI from the telecom room to the CO and it looks all good for them.