reinstalled following The procedure above with no improvement. changing values in preferences resulted in no improvement. No fragmented files or anti virus running. TI firewire card is firewire only and Saffire 56 the only thing running on firewire. Works perfectly with m-audio 1814. Haven't tried 3.3 software as it's not listed on the saffire 56 page, only 3.2. Not using legacy driver. By the way, THANKS sincerely for chiming in and helping a long time Sonar user. Most of the time my stuff works, but good to have support when it don't! :)

http://uk.focusrite.com/downloads/saffire-mix-control-33
 
"The latest version of Saffire MixControl. This installer includes all necessary drivers and software to run the firewire Saffire range of Focusrite interfaces."
 
I just don't think they updated the 56 page, you could drop Focusrite an email about this in case they removed it because of some specific issue.
 
I would suggest a clean install with a reset as per my previous post (and always backup).
And please supply the full make/model of the Ti firewire card, also please play with your settings as in #5 (but no point until you've updated mix control), plenty of stuff here about tuning the latency side as well.

Stop, go no further !

FYI the Mix Control v3.3 does NOT work with the LS56 (you can only download v3.2 from the LS 56 download page).

I asked the question some time ago and Focusrite confirmed by mail that Mix Control v3.3 is NOT compatible with the LS 56. They did not say why.

Cheers,
Jerry

Why the heck do they state "The latest version of Saffire MixControl. This installer includes all necessary drivers and software to run the firewire Saffire range of Focusrite interfaces." on my link...?
 
Focusrite definitely needs to amend this... thanks for feedback Jerry.
 
Previous advise still applies then only with v3.2 - Cheers (I didn't have any issues with 3.2 either).

I just emailed Focusrite about this.

The only other thing to verify I may have missed is any onboard FW adapter disabled in BIOS?
 
I just looked at the Focusrite site and indeed the 3.2 version is the last for the 56 (http://us.focusrite.com/firewire-audio-interfaces/liquid-saffire-56/downloads).
 
It may be well worth it to contact Focusrite directly about this issue.
 
Edit: Alex said he already did. Thanks Alex.

CakeAlexS
I just emailed Focusrite about this.

Be interesting to see what reply they give you.......

As of 2minutes ago still only v3.2 available for the LS 56.

That being said, for me the software and drivers are rock solid.

Cheers,
Jerry

My money is that it was supported in 3.3, then they found a major bug with it and the 56, so they edited the 56 web page to state just 3.2 and forgot about the other pages.
 
Not including drivers (or reliable drivers) in 3.3 makes no sense otherwise. If they wanted to drop support for the 56 then you would have expected that to happen in MixControl 4.x
 
Either way it's a bit amateur, but then again they've never had the best looking support website. Best hardware and drivers though.

I feel bad that I called attention to the 3.3 version of the driver. I made the same assumption, based on the Focusrite wording, that 3.3 would also apply to the LS 56. Thanks, Joakes, for setting us straight about that.

The statement that the Liquid Saffire 56 'does not work' with Mixcontrol 3.3 is not exactly accurate.  We did remove the 3.3 version from the LS 56 download page due to it causing the second bank of ADAT inputs to be distorted.  Since the Liquid Saffire 56 is the only unit in the line that suffered from this issue, v3.3 was left on the other product pages.  The issue with the second ADAT bank is now corrected in MixControl 3.4 which is now in the public beta phase and can be downloaded here:
 
http://beta.focusrite.com/releases/saffire_mix_control/
 
In regards to the OP, I do not believe that running MixControl 3.2 is the cause of your issue.   You have already tried quite a bit of troubleshooting, but I didn't see you say whether or not you tried checking for DPC latency as was previously suggested.  Aside from testing for DPC latency, I think the best thing will be to get in touch with the Focusrite Support team so that we can work with you 1 on 1 to resolve the issue.  You can contact us with this form:
 
http://global.focusrite.com/answerbase/contact