I'm afraid that feature might not be a good idea. That is, it would be greatest if it worked for jackd, in general.
You know, that jack was designed to work against only one sound-card device and its ALSA backend driver is coded explicitly with that rule in mind, so to speak. You can of course make it work with combined virtual devices given that you can get it all correct magic on the asoundrc configuration file.
It's all highly tricky, unreliable and prone to too many disparate problems that depends on each particular device setup and configuration. Not speaking that you'll have to tune for high-latencies, something that JACK is not well suited or overkill :) Not easy, not even for the expert ALSA technician which I am not ;)
I'm afraid that feature might not be a good idea. That is, it would be greatest if it worked for jackd, in general.
You know, that jack was designed to work against only one sound-card device and its ALSA backend driver is coded explicitly with that rule in mind, so to speak. You can of course make it work with combined virtual devices given that you can get it all correct magic on the
asoundrcconfiguration file.It's all highly tricky, unreliable and prone to too many disparate problems that depends on each particular device setup and configuration. Not speaking that you'll have to tune for high-latencies, something that JACK is not well suited or overkill :) Not easy, not even for the expert ALSA technician which I am not ;)
Cheers