Interface startup issues & plug in info needed.

Question

I use a Presonus firestudio mobile for my Logic software.Each time I turn on my Mac & try playing a project on Logic ,I dont hear anything through the interface.I dont even see the meters going up.But then I close Logic & open up studio One DAW,I hear the music on the interface.I then shut down Studio One & go back to Logic & everything is back to normal & I hear the music hrough the interface.Can someone tell me why this is happening of late & how to set it right.I always have the audio set up to go through my firewire interface on Logic by default,but something blocks the sound from coming through Logic or even the built in speakers of the Imac.
The 2nd question is some of my plug ins (3rd party) that were once found on Logic does not show up anyore.How do I go to the plug ins page on Logic to see if it is activated or not?
Thanks.

Answer 1

Ministrel wrote:
I suddenly had a flash & remembered what I did last time to get it working normally .INITIALIZE was the magic! I did it & then a note flashed asking if i wanted to change some cycle to 1/96 (it read some bla bla but I remember a 'clock' in the statement!).Whatever happened when I clicked it I dont know but it worked fine with the audio coming out of the mac,after which i selected the interface.Is there anyway that I can do this in future without having to initialize it? Do the words'cycle' & number 1/96 ring any bell to you? If not is there an email ID for Logic support so I can check with them?
You also mentioned leaving Mac's audio preference to built in.Does that mean you connect your Mac's output to the studio speakers when running Logic or do you get the sound of Logic via the interface you use?
Are the studio speakers self powered? If so they should be connected directly to the Interface  audio output.
You don't want to use the $2 audio chip in the Mac when you have an audio interface with much better sound.
What  are you initializing?  The Presonus?  Not sure what the "cycle 1/96" was all about.
Under Logic  preferences/audio
Set both Input Device and Output device to the Presonus.
Set the I/O buffer to 256.