[LAU] Multiple sound cards

[Alf Haakon Pietruszka Lund]

Hello list!

I am on (K)Ubuntu Studio 20.04) and needed a couple of extra in- and 
outputs, so I connected 2 USB audio interfaces to my computer (a 
FocusRite Scarlett 2i4 and an Edirol UA-25ex - they're old, but reliable 
devices).

Through Studio Controls I set the Scarlett as master device and started 
Jack, then I experienced recording and playback with Ardour in (as far 
as I can hear) perfect sync.

I was amazed at the ease of this setup and the problem-free routing of 
audio signals, so just for testing I split a stereo source recording one 
channel on each device to one stereo track in Ardour. To my ears, the 
sync is still perfect.

However, from this article 
https://jackaudio.org/faq/multiple_devices.html it seems I have to 
expect sync problems over time unless I do some manual configuring using 
the alsa_in and alsa_out clients.

Is this still valid?