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The best technique is the same that works for all protests – lots of feedback, over long periods of time, from a variety of people.
I’ve seen it work on Qobuz, and many Roon Ready/Roon Tested partners. You all are a minority, but you spend big compared to the average mass-market user, and you carry respect. Believe me, they want you more than you want them. It’s true of every service.