Interim solution:

Those looking to disable System Integrity Protection may do so via the csrutil command line utility in recovery mode:
csrutil disable
To compliment its new role, csrutil now offers a higher level of customization; Individual aspects to System Integrity Protection may now be enabled or disabled individually:
csrutil enable \
--without kext \
--without fs \
--without debug \
--without dtrace \
--without nvram
If you would like to prevent the modification of your boot parameters, for example, but without the filesystem lockdown getting in your way, this would now possible like so:
csrutil enable --without fs
Anyway, spread the word, and enjoy!

in this case you have to disable the kext signing check with

csrutil enable --without kext

Here we are almost a year after the release of OS X Yosemite and still no properly signed kext for running Presonus Firewire products. What is the problem with signing the kext? Nobody should have to run their system with compromised security just to use Presonus gear.

As many have discovered, the same issue exists in El Capitan Developer Beta 8. I have to switch off kext validation with System Integrity Protection just to use my FireStudio Project with my Mac.

Signing a kext is extremely easy to do in Xcode. The current driver works in both Yosemite and El Capitan but only if system security is compromised. I'm not asking Presonus to rewrite the driver or do anything other than properly sign the kext when they compile it. Apple provides easy step by step instructions on how to sign software in XCode.

A year ago Gary from Presonus support gave me the excuse that Yosemite hadn't been released yet for having the unsigned kext. That in spite of Apple guidelines recommending signed kexts for Mavericks and a clear warning that unsigned kexts would not be acceptable in subsequent versions of OS X.

Here we are September 4th 2015 and still no properly signed kext from Presonus. Yosemite has been out for close to a year.

Even worse the Presonus support page claims Yosemite compatibility for Universal Control v1.7.2 - Mac. That's only true if the end user knows how to disable kext security in OS X.

Please advise what it takes to convince Presonus to do the right thing and sign the kext for the OS X driver. It shouldn't take more than a few minutes to recompile the kext and it would make using the Presonus products safer and easier in OS X.


Regards,
Philip

I totally agree.

Presonus please take the time to properly sign the kext for the OS X driver. We'll appreciate it.

thomasgusenleitner wrotein this case you have to disable the kext signing check with

csrutil enable --without kext

You also have to be in recover mode. (Reboot your Mac and hold down Cmd-R on restart).

http://www.presonus.com/support/downloa ... io-Project

Downloading the latest OSX installation packet 1.7.3 should do the trick on El Capitan.