Off the topic of best audio card for your requirements, I wanted to mention that there are two different ‘generations’ of “Official 7” touchscreen", I think known as Touch Display and Touch Display 2, and they are quite different. The original TD will generally work with Zynthian, TD2 will come up in portrait mode, and to the best of my knowledge, although the display can be right rotated to landscape, the touch screen cannot. I submmited a 3 file set of pull requests to add the support for TD2 in landscape about 10 days ago. It has not been accepted (hopefully), yet.
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