New mac book pro 15" late 2011 and logic pro user 9.1.7 losing sound in logic on reboot and start up any help please ?

Question

keep losing sound when reopening logic would like to now if this is a lion related problem or logic , setting do not change.
All ways" save as" and name project and regularly "save".
this is really getting on my nerves i've swop to mac on advice it's a far more stable platform for audio, daw's and music.
I tend to use my computers in short 20 to 30 min sessions several times a day.
i had to revert to my windows computer because as well as learning logic pro and trying to figure out a new operating system it seems apple have adopted microsoft's approach, putting out a operating system and getting the hobbie techs to tell them whats wrong, this is like buying a car or house that you haft to finish building or wait for the contractors to come back to you, in there own sweettime.
not impressed.

Answer 1

I have check hardware and everything seems to be ok.
How?  Did you run the AHT from system DVD #1?
after that first restart i get a blue screen.
You updated to OS 10.6.8 and everything else that needs updating?
If you did not repair permissions and restarted your installations, do the following:
Disconnect all devices from the computer then do the following:
Boot up from your Snow Leopard Install DVD while holding down the "c" key.
Select the language you wish to use, and then choose "Disk Utility" from the menu bar.
Your HD should appear in a panel on the left hand side of the window which opens. Select it and then click on the "repair disk" button in the right hand section of the window.
Once this process has been completed restart your computer and repair permissions directly from Disk Utility.
If Disk Utility is unable to complete the repair, you will need to use a stronger 3rd party utility like DiskWarrior, Techtool PRO (not Deluxe) or Drive Genius.
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How large is your HD & how much space do you have left?