yosemite and internal HDD question

Hi All,
I am getting a strange issue where I can not see my internal drives when I boot from USB.
If i boot normal, then (obviously) I can see all internal drives and everything is fine.

This is a 'new' issue and it just started happening. Nothing has changed.
Booting from various OS backups and also tried using various USB inputs on the computer (mac Pro 2010 5,1)

Internal drives are 4 SSD (I have the trim enabler running) and 1 HHD connected to one of the DVD connections.

I can boot normal (boot from internal SSD) and see all drives, everything.
But if I boot from a USB backup, I can no longer see any internal drives (including the regular HDD connected to the DVD port)

Everything has alwayse worked in the past, 100%
This is just resent now that I can no longer see any internal drives when booting from a backup USB drive.

Anyone have any clue at all as to what is going on?

thanks
Kurt

I just got it to work again by being able to see the internal drives..
I disconnected all USB external DVD players, Changed the USB cable, hooked the USB cable to the front of the mac.

Ill need to back track and see what the culprit was, but as to why this was happening I still have no clue.

thanks
Kurt

Hi Kurt,
Not sure if this will help, but if you are booting from a different drive, this will change your system preferences. Make sure after booting into different drive, you go into Finder preferences and check the box the drives you want to see.
Hope this helps, Greg