I'm not sure I understand. I've since moved to Qobuz, but I was talking about, for example: when you set Tidal's quality setting to the mid-level 'Hifi' - and choose a file that is not labeled 'MASTER' (because you want a simple FLAC).This is incorrect. If it is a MQA track; it shows on the MQA indicator of my EX5.
I have been listening to MQA Masters for the past few days. I ran into a single FLAC file it seems, because the MQA light was not lit. Otherwise everything is MQA, there are a couple different versions but it works well using hardware unfolding.
I would imagine the SU-8S works the same way.
In this case I think the MQA light on the DAC is always off - even though there has been MQA encoding done on many of these non-MASTER files...
Ie., many of these non-MASTER files are FLAC containers for partially unfolded MQA files, not simple lossless FLACs.