A problem running FL Studio via CX is often the high latency. Either try to lower it to the cpu max via the setup-panel or, if it isnt low enough, try installing WINEASIO, this will give you a fully implemented Asio Driver in Wine. If you cant get it to run in CX try it in Wine first and see how it works. (Wineasio will send it sound over jackd, so jackd will be required!)
Get Wine-Asio here: http://sourceforge.net/projects/wineasio/
For 64bit users it might not work, instead use this version: http://people.jacklab.net/drumfix/wineasio-x.tgz
For Debian/Ubuntu users there is a deb file availiable: http://homerecording.de/~4damind/hr/wineasio-x_0.3.deb
CATION! The deb file is most certainly out of date and maybe not functional on 32bit systems, as i have not tested it yet.
If not in your Distros Repository, get jackd source here: http://jackaudio.org/download
If not in your Distros Repository, get qjackctl source here: http://qjackctl.sourceforge.net/
Get the wine-dev files here: http://sourceforge.net/project/showfiles.php?group_id=6241&package_id=77449
For a decent jack interface get the qjackctl package. It will provide you with the jackd sound server deamon (if your distro solves dependencys automaticly, other wise you have to get jackd seperate) and a jack interface. Be sure to configure and start the jackd BEFORE launching FL Studio. The you still might have to patch the FL Studio output to the jack input, which can easily be done via the connect panel in qjackctl.
For Compiling the Wine-Asio Driver you will need the asio.h file out of the Steinberg Asio SDK, which is not under any free licence. You will have to create an account at Steinberg to get it. (As its listed under 3rd Party devel tools)
Also required for compiling is the wine-dev and libjack-dev.
Further Instructions will be included in the winasio source code.
IMPORTANT: If you do not have wine installed you probably have to take the generated wineasio.dll and copy it into the /windows/system32 folder of your FL bottle.
Then when doing the 'regsvr32 wineasio.dll' as stated in the wineasio README you have to put the WINEPREFIX command in front (even if you have wine installed [i] 😉):
# WINEPREFIX=/home/user/.cxoffice/flbottle/ regsvr32 wineasio.dll
After succesfully implemented wineasio, you only have to use winecfg and select ALSA as the ONLY soundserver. Then in FL Studio select the WINEASIO driver.
To Start FL Studio: 1. Start qjackctl
2. launch jack server via qjacktl
3. launch Fl Studio
Thats about it. Dont hesitate to start n bump a post on the forum on the topic if you need help.