So my friend lend me his Behringer UMC202HD and I am pairing it with my Focusrite2i2 to compare zita-j2a and alsa_in, I just played bass thru a DI box with two outputs one for each interface. About zita-j2a, well it initially does perform better as it seems to have no noticeable delay between the main (jack) interface and the one coming thru zita-a2j but after some 10 or 20 min it stops working, it happened every time. On the other hand alsa_in does have a little noticeable delay but it is usable and it is been rock solid stable, left it running all night and I came back to computer and it is still working.
I am not sure if all these details about alsa_in and zita-a2j should be on a different forum or just a different area of this forum but my I idea was to share my comments for those using Ardour trying to use 2 interfaces. I will try to do my best to investigate and try to get zita-a2j running stable as alsa_in does and just come back with my final comments to avoid making this a ling thread.
By the way, the UMC202HD did a good job recording a drum set with two mics in a bedroom, I know Behringer gets a lot of bad comments but this interface gets the job done.