What kind of adapter are you using for the Mini Display port? The 24'' Apple Cinema Display works fine with my 2017 MBP and this adapter: https://www.amazon.com/gp/product/B082KKJVGB/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1I just got Mac Mini M1 and it didn't work with my 24 LED cinema, called Apple support they asked me to bring my display to the store so they can see what's up. Thich is barely an inconvenience... The sound worked thought but no image in the display. IT Means USB 2 is ok, Thunderport seems to be the main issue. I honestly have no clue what to do because this is my working display and you can't even trade it in, only recycle. FOR FREE. Sweet Apple.
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