Synchronisation trouble with ViewPixx after latest Psychtoolbox update

Hi all, 

I had been having trouble with some stimulus triggers for my EEG setup with the ViewPixx / Neuroscan NuAmps setup I have, so I tried updating Psychtoolbox. Now I have a host of problems I didn't have before, and my triggers still aren't reliable. 

Main problem: Psychtoolbox reports synchronisation failure where it didn't before: 

PTB-INFO: OpenGL-Renderer is ATI Technologies Inc. :: ATI Radeon HD 5770 OpenGL Engine :: 2.1 ATI-1.24.39

PTB-INFO: Renderer has 1024 MB of VRAM and a maximum 1001 MB of texture memory.

PTB-INFO: VBL startline = 1080 , VBL Endline = 1123

PTB-INFO: Measured monitor refresh interval from beamposition = 16.667300 ms [59.997719 Hz].

PTB-INFO: Will use beamposition query for accurate Flip time stamping.

PTB-INFO: Measured monitor refresh interval from VBLsync = 8.333857 ms [119.992460 Hz]. (50 valid samples taken, stddev=0.084366 ms.)

PTB-INFO: Reported monitor refresh interval from operating system = 8.333333 ms [120.000000 Hz].

PTB-INFO: Small deviations between reported values are normal and no reason to worry.

WARNING: Mismatch between measured monitor refresh intervals! This indicates problems with rasterbeam position queries.


One or more internal checks (see Warnings above) indicate that

queries of rasterbeam position are not properly working for your setup.

Psychtoolbox will work around this by using a different timing algorithm, 

but it will cause Screen('Flip') to report less accurate/robust timestamps

for stimulus timing.

Read 'help BeampositionQueries' for more info and troubleshooting tips.

LoadIdentityClut: Warning: GPU low-level setup code for pixel passthrough failed for some reason! Using fallback...

LoadIdentityClut: ATI Radeon HD-5000 Evergreen on OS/X detected. Using type-2 LUT.

I'm using MATLAB R2012b on Mac OS 10.9.5. 

Second problem: The "DrawText" function doesn't want to work properly: 

PTB-WARNING: DrawText: Failed to load external drawtext plugin [dlopen(/Applications/Psychtoolbox/PsychBasic/PsychPlugins/libptbdrawtext_ftgl64.dylib, 10): Library not loaded: /opt/X11/lib/libfreetype.6.dylib

  Referenced from: /Applications/Psychtoolbox/PsychBasic/PsychPlugins/libptbdrawtext_ftgl64.dylib

  Reason: Incompatible library version: libptbdrawtext_ftgl64.dylib requires version 19.0.0 or later, but libfreetype.6.dylib provides version 10.0.0]. Retrying under generic name [libptbdrawtext_ftgl64.dylib].

PTB-WARNING: DrawText: Failed to load external drawtext plugin 'libptbdrawtext_ftgl64.dylib' [dlopen(libptbdrawtext_ftgl64.dylib, 10): image not found]. Reverting to legacy text renderer.

PTB-WARNING: DrawText: Functionality of Screen('DrawText') and Screen('TextBounds') may be limited and text quality may be impaired.

PTB-WARNING: DrawText: Type 'help DrawTextPlugin' at the command prompt to receive instructions for troubleshooting.

Neither of these problems are ones I had before updating Psychtoolbox. 

With the triggers, I suspect it is a problem with flip timing, but I've tried everything without success so far. My code for the triggers is taken pretty much straight out of the DataPixx demo code: 



[vbl, ~, ~, Missed] = Screen('Flip', w, vbl + waitduration); 


Datapixx('RegWrRd');   % Update registers for GetDoutStatus

status = Datapixx('GetDoutStatus');

Datapixx('SetDoutValues', 0);


waitduration is defined as ifi*.8, so the flip doesn't miss - I tried ifi/2, but that cause too many misses. 

Any help would be greatly appreciated. I'm supposed to be piloting this experiment tomorrow, and I'm kind of desperate.