1.7b3 on Liuon 1.7.2: Display switch
 

Dear developers and readers

I have the following setup:
Mac Mini Lion Server as Workstation
Lion 10.7.2 Developer 11C57
2x Samsung 24" Displays over DVI direct connected on the Mac Mini
DisplayLink driver 1.7b3
2x SAMSUNG U70 7" Display over USB (Connected to Belkin 7-Port USB Hub)

Problem:
I did setup the Displays that way, that the two big ones are placed next to each other. The two small ones are placed also next to each other but below the big ones. Now every restart (warm or cold) the position of the two small displays is switched in between the two. That means that after the placement of the displays, from left to right and from top to bottom is this way.

------------------------------------------------------
|----------Display 1 Big | Display 2 Big----------|
------------------------------------------------------

|-Display 3 Small | Display 4 Small-|
-----------------------------------------

Now the placement of Display 3 and Display 4 will be changed so that Display 4 is on the left side below Display 1 and Display 3 is on the right side below Display 2. The real crazy thing is, that the content of the of the displays stays where it is during the placement of the Displays 3 and 4. I have to do this replacement because the direct movement of the cursor is not possible anymore.
Is this a bug of the DisplayLink 1.7b3 software or is it a other problem link som problem of the SAMSUNG U70 Displays?

Thank you all for anyones replay and feedback.
Regards
Thomas Thaler

The display arrangement is managed by the OS and it's saved in the /Library/Preferences/com.apple.windowserver.plist. You could try to delete this plist file, reboot the machine and check if the issue is solved.

Thank you fro your replay.
But your suggestion didn't fix the problem.
Still, watch login, the placement of display 3 & 4 switches in-between them.
Does anyone have some other suggestions?

I've had this problem ever since I've had my DisplayLink devices.

I've got two DL devices and three Dell 20" monitors (2 x DL + 1 x DVI via Display Port adapter). I have a 2011 MacBook Pro i7 running Lion.

The monitors are arranged left to right as DL1 - DVI - DL2. On each restart of my MacBook it's a lottery as to where the DL attached monitors will be. Sometimes it's correct, sometimes they are swapped, and very occasionally they both appear to the left or right of the DVI connected monitor. Also, from time to time, the desktop wallpaper will go back to a previously selected one.

As I said, this problem has been present with DisplayLink drivers v1.5 (on Snow Leopard), v1.6 (on Snow Leopard x64) and v1.7 (on Lion). I've always considered it a minor annoyance but nonetheless there's something not quite right somewhere in the mix between OSX and the DL drivers.