For DSP troubleshooting you should know what you have and what you need.
- in Hardware Modules form under Hardware you can see the DSP modules installed
( I just had a problem with an old DSP module installed in a CX II and was not used by the system at all, after upgrading to Rel 6 it generated an alarm, had to remove the card)
- next check your licenses, if you have licenses enabled that require DSP II cards and you don't have it installed you get an alarm (Fax and compression)
- check the number of voice mail ports programmed and max allowed based on your configuration (tech handbook)
If you have a quad DSP and one chip is dead that would equal 25%.