that is an interesting one indeed..
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the mix wont work, because when you set that on 100 % and it will fill the remaining time with duplicates (and right so imo)
now what i though was:
sort by rating > take the amount you want > and shuffle
the problem here is of course that it will always use the same files with rating 3 everytime
so: shuffle > sort by rating > take the amount you want > and shuffle
this does not work because mc's wizzard thinks two sorts behind each other do not work and one is removed.
there is a trick needed
so: shuffle >limit to 100000000 items> sort by rating > take the amount you want > and shuffle
works
code:
[Media Type]=[Audio] ~sort=Random ~n=10000000 ~sort=[Rating]-d ~t=45h ~sort=Random
hope its what you are after
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gab
ps: its fun to fool a wizzard. but as a side note, the good, or maybe bad, thing is that when your amount of 4 and 5 rated stars is bigger then 45 hours, the smartlist will take all 5 star files and add 4 stars till its at 45 hours again.