Sonar 8 Studio Edition, Windows 7
 
I just purchased a PreSonus AudioBox 22VSL USB interface, and am having some issues with the audio drivers when I try to use it with Sonar.
 
When using the WDM drivers, I can only record at 16 bits.  When I switch to 24 bits the meter pegs in the red and I get a bunch of hiss and noise.
 
PreSonus recommends using the ASIO drivers, but when I switch to ASIO I get no input whatsoever.  Also, the the bit-depth selection and the buffer-size slider are grayed out after I apply the ASIO drivers.
 
I think I solved the problem by using the WASAPI drivers.  When using these, the wave profiler runs fine, all bit-rate and sample-rate options are selectable, and the few test tracks I recorded came out fine.
 
So my (hopefully academic) question is:  What's the difference between ASIO and WASAPI?  Should I be using the ASIO drivers as recommended by the manufacturer?  And if so, why isn't ASIO working in Sonar on my machine?
 
Hopefully I can just use the WASAPI drivers since they seem to be working fine, but I guess I want to know if there might be some problems I haven't encountered yet.  I'm also just curious about these issues with the other drivers...
 
Many thanks,
G.S.

  Use what works for you. Different setups work differently with the various drivers. It is a good idea to test all the drivers available to see which work best in your environment. Presonus does recommend using ASIO but if you are getting good results using something else go with it. The buffer-size slider is not used with ASIO drivers that is why it is disabled in SONAR. In the case of Presonus, to alter the buffers use the Presonus AudioBox tool, the config tool supplied with your interface. Audiobox may also help you figure out your ASIO input issues.

Hi Slim,
  is the onboard soundcard enabled? 
This can be the reason for driver conflicts etc.

bit-depth selection and the buffer-size slider are grayed out after I apply the ASIO drivers.

Right because you set up ASIO devices using the device's ASIO control panel, not Sonar's. This is normal. 

Thanks for the help everyone.  Yes I have disabled all other audio devices, but have not uninstalled them.
 
The PreSonus has a "mixer" interface with some setup options.  Those include sampling rate and buffer size, but NOT bit depth.  However, I discovered there are more setup options you can access under the device properties in the Device Manager.  This DOES include bit depth as well as sampling rate. 
 
So, I made sure that EVERYTHING was set to the same bit depth and sampling rate (24-bit/48 kHz) -- in the device's graphic interface, under device properties, and under the Audio and Global options in Sonar.  Still no dice, no signal at all.
 
I'm perfectly happy using the WASAPI drivers instead.  These seem to have the added advantage of allowing me to adjust all of the parameters from within the DAW without having to open both the device interface and/or the device manager.
 
Still, this kind of stuff just BUGS me.  I will definitely contact PreSonus and see what they have to say.
 
Thanks again for all your help.   

If Windows is set to use the Audiobox as a playback/recording device, make sure that the bit depth and sample rate match there as well. This can cause the interface to switch settings in the background. FWIW, I have a 44VSL and was able to get it working properly at 24/44.1 using WDM/KS. I did have to uninstall/reinstall the driver once though. If it keeps giving you trouble, I'd recommend that first. Make sure you completely remove any Presonus files before reinstalling and unplug the interface until the installer tells you to plug it in. One other thing I've learned from Presonus: The driver is apparently sensitive to which USB port you use and you should not switch ports without reinstalling the driver. Regards, Dan

Nothing useful to add.
Dan, good to see you around.
I saw your name, and had to go to your soundclick page.
Voyager Leaves Sol is a long time favorite, and still gives me chills.
The others are pretty tasty as well.
Do you have anything in the works?

Not yet. Just recently finished setting up the new DAW (from Studiocat). My old one died about 3 years ago and I had other priorities. Hopefully, I'll sit down and stare at a blank project soon ;) Regards, Dan

The PreSonus has a "mixer" interface with some setup options.  Those include sampling rate and buffer size, but NOT bit depth.  However, I discovered there are more setup options you can access under the device properties in the Device Manager.  This DOES include bit depth as well as sampling rate. 

I just installed my 22vsl and having the same issues so after reading this I went to device manager and can find no way to change the bit depth (crazy as hell this isn't in the software...seems much more important than the onboard fx and stuff).
Also in a 24/44.1 project, Sonar X2 is showing 16/48...if I close the project and select 44.1 in the 22vsl software and then open the project back up, X2 switches the 22vsl back to 48K.
Any suggestions would be very much appreciated,
Randy

not an insult, just the truth.
the audiobox is not the best interface in the world, the focusrite Safire 6 is much better and only a few bucks more.
the problem with the audio box is the levels stream too hot.
you cant control the input in sonar, because the box decides the input level.
I wrote presonus about it and they said they were aware of the issue and the fix was to but a DI box.
sure, im going to buy a DI box for another 30 bucks.
so I returned it and got the focusrite Safire 6 usb.
the Safire's pres are award winning focusrite, they sound it as well.
its like a pre amp, a nice warm sound.

do a search here on the forum, youll see a few threads about it.

http://forum.cakewalk.com/tm.aspx?m=2233313&high=audiobox