I've never used your particular interface, however as far as I know, Windows (any version) will only allow you to run one ASIO driver at a time, same with Cubase. Being it's a USB interface, you can certainly have 2 of these interfaces connected to your PC, but I don't see that translating to using both at the same time.,,that is UNLESS Tascam has drivers that are specifically designed to do so, usually called multi-client drivers. (I have NOT researched your interface and it's drivers mind you!) I'm not sure how Windows, or Cubase can differentiate between two US-144 USB interfaces?
I do know that my Aardvark Q10 PCI interfaces DO have multi-client drivers, which allow me to run up to 4 of them in a single PC simultaneously, for up to 40 I/O's directly to the DAW. I once had 3 Q10's installed/running fine (I only had 3 PCI slots in the PC available).
I would like to be proven wrong about not being able to use multiples of your Tascam US-144 (but again I don't know about it's drivers). My own Tascam FW-1884 & FW-1082 interfaces DO NOT have multi-client drivers available. By the way, I'm running these Tascam FW units (one at a time of course) under Win 7 64 bit Pro with their own separate respective 1.80 drivers for each. I also am a Cubase user.
All hope is not fully lost yet, as a 'potential alternate' solution to using two US-144 units together, is to simply connect them via their digital audio s/pdif coaxial RCA type connections (use a digital audio cable with RCA's - I use Hosa s/pdif cables myself). Plug the 1st US-144's s/pdif OUT, into the 2nd US-144's s/pdif IN. The 1st unit will act as a sub-mixer, but only providing a stereo audio signal sub-mix out. BUT, to do this in the 1st place, your US-144 may need to be able to be used in a 'stand-alone' mode...OR it may also be possible to set up the 1st interface's routing via it's USB to your PC, and if it can retain the routing settings, use it as described above as a sub-mixer. You will NOT be able to get each of the units inputs & outputs directly into your Cubase DAW however, only the 2nd unit will be able to send it's I/O's directly to Cubase, while the 1st unit will only send a sub-mix into the 2nd unit, which can be passed on via that 2nd units inputs to it's outputs. Clear as mud?
In the end, if you simply must have more inputs and outputs going directly into the DAW separately, you may have to get another interface after all. But you can also buy a 'used' interface. I even bough tboth my Tascam FW-1884 ($100) & FW-1082 ($150) used from eBay. These things were well over $1,000 when new in their day. But my PC has built in 6-pin powered Firewire, with the highly recommended Texas instruments chip.
