unable to use 002 after start up

[nitogrenada]

pro tools 6.2.3
digi oo2 with new firmware
g5 computer with 1.5 gig ram
bundled plug ins

here is my error message
"lost communication with the 002 unit. Please try increasin H/W buffer size or removing plug ins (-6097)"

any thoughts are appreciated
nito

[nitogrenada]

digi 002 has new power hanrness and worked bequtifuly a few months aago would be able to record and everything

since then i have used cpomuter for other things

hard drive 160 serial and 250 serial both internal

[nitogrenada]

experiments i have tried to solve this problem
1) changing the firewire cable
2) reinstalling the firmware on the digi 002
3) going through and chaecking the H/W buffer size increasing and decresing it
4) i have pro tools 6.2.3
5) i am running mac os X 10.3.3
6) the power harness is new
7) the systme used to work fine several months ago
8) i have installde some new programs (neverwinter inights, i life - includes GARAGE band)