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sequences of cycles with a decay characteristic or an envelope

I guess that is where the confusion about frequency comes from.
The frequency in PLAY SOUND is the repeat rate of your sequence or sample, not the frequency of the sound itself. I don't think that use was anticipated when Type U was added.

As you have seen my second example shows that if there is more than one cycle the frequency of PLAY SOUND gets multiplied by the number of cycles in the array.

Hi Phil,
Thanks again for your advice.

  phil99 said  

I don't think that use was anticipated when Type U was added.

Perhaps Peter created something he didn't realize how valuable it could be?  
I think the manual should explain this better.

I've shown an example of how to use it in PicoPongo.
Kind regards
Michael