I am running 2 Studio-Captures synced. The drivers show up in Sonar that both interfaces are running but in some other programs it only allows access to them one at a time.

BobF
The only way out of this that I can think of is to add a Mac to the mix for tracking with these other devices.  But that would be expensive and I'm not sure if the alleged I/O aggregation capability of Mac really works as well in practice as the stories I've heard.
 
Maybe Windows 10 will address this.

First there's the clocking issue.  All devices would have to share a common clock source.
Otherwise, track's recorded across units would drift apart over time.
 
Then, you've got potential offset (in samples) for each different device.
You only have the ability to compensate for a single device's offset.
 
IOW, Even if Windows 10 enabled aggregation... it still wouldn't be a practical/elegant solution.
For that to happen, the ASIO spec itself would have to change.

Audio interfaces are just like 'Highlander' - there can only be one!  (Although they also differ in that they tend not to go about chopping people's heads off).
 
The reason for this is that there can be one, and one only, master word clock in the system (as Jim indicates above).
 
So let's say you have one ASIO driver interface hanging off the end of a USB bus, and another sitting on the PCI bus.  How then are their clocks to be sync'd, i.e. one slaved to the other?  That is a damn good question and there is not, as far as I'm aware, an answer to this.

jih64
M Audio, up to 4 Delta 1010's, Delta 44's, Delta 66's etc etc . . . .
I also believe you can mix, 1010's  44's, 66's etc (could be wrong on that' but I'm sure I read it, could unplug a 1010 and try it, but I aint gonna)

you are correct.  m-audio's delta drivers allow for "mix and match" among delta devices only, tho.

mudgel
 
Another way to do it also is to have a single interface that supports ADAT IO so that you can connect multiple additional inputs/outputs which will show up in your driver and thus in Sonar.

I have a question about this, please?
 
I have never used an adat I/O although I have 2 compatible devices...
If ADAT is the chosen driver, do the brands still matter?
Can these devices be chained?
 
Is ADAT a reliable/quality/high fidelity interface?
Any info greatly appreciated.
 
MEL

adat is not a driver, nor does it require a driver.
Regardless of brand, any interface with adat input can be chained to another device that sends channels via adat.
It is a type of digital connection that carries 8 channels of audio at normal sampling rates.
 
 

Just to expand on the ADAT side of things, if you use ADAT devices you still need an audio interface to connect the ADAT stuff to the PC.

My interface is an RME UFX, which has a Focusrite Octopre ADAT unit connected to it to add another 8 ins and outs. The RME and it's driver handles all communication with the PC, and the RME Totalmix software mixer does all the input and output routing side of things. The Octopre neither has nor needs a driver because the DAW never sees it directly but addresses it through the RME.

I could add another ADAT, made by any manufacturer, if I needed it and the setup would still work in exactly the same way. Some PCI audio interface cards are simply ways to connect a lot of 8-channel ADAT units to a PC, with the card being the audio interface as far as Windows and DAW software is concerned.

Thank you for your replies,
I'm grateful for the info.
 
Both interfaces have adat  support and both are already connected to my DAW.
One is an internal pci w/breakout box(echo Layla 24), and the other is
internal firewire w/breakout box(saffire pro 40).
I'm not planning to chain them but it's nice to know I could if need be.
 
Thanks
MEL