@whale-av Thanx so much. I'll check when I'm back in a few days.

At least it's the first step before going further. But I was struggling a long time with this and right after posting my question I found a solution (only the playhead position is not working, but I'll look at it now). Typical = coming back after a night break often leads to a solution. At least starting fresh is always beneficial compared to trying hard to find a solution since hours and being trapped.

Ok I found the solution!!!!

Here is the test patch (part of a much larger patch). Without the folder with the samples as the first sample is too big to be posted here.
soundfiler issue.pd.zip

I spent a day and a half trying different methods without success. I searched the forum but I can't find an answer to my exact problem.
When I used the method "open samples/xxx.wav, 1" and then "readsf~" to open an audio file chosen randomly between different files (xxx being 0 or 1 or 2 etc etc) all worked fine.
But I have to be able to change the speed of the audio file playing, and the "readsf~" doesn't allow it.
I have to mention that my audio files are quite long and I chosed a length limit of 4min50sec (it seems to be the limit for the audio file to play without issue).
As far as I understand, I need to use "soundfiler" to be able to change the speed of an audio file.
This is working fine with one audio file that is loaded when the patch is getting opened.
But as soon as I want to load automatically a different audio file (chosen randomly in a list of audio files), then it won't work.

SCREENSHOT 1 = If I first chose the file and then read it (adding a delay or not between events), the file will not read, it doesn't appear in the array, it doesn't play.

SCREENSHOT 2 = showing that if I don't chose first the file between different files, then it works. Array ok and audio plays.

Is there a solution for what I'm trying to do?
I need to solve SCREENSHOT 1 to be able to develop the patch further.

I misinterpreted a previous comment. I thought I should add a line break but it was the opposite. I also thought "unpack" was limited to 2 elements. My bad. This is why I took a break, cause I spent too much hours focusing on my issue and confusion did arise. I struggled a little bit but now all is working fine.
Stepping back is always for me the solution. And also dare asking.
Thanks a lot for all the help, the patience and the reactivity.
I very much appreciate.

@freq63 said:

Here resumed as a picture if easier to understand:

Aargh. Can't edit my post so here my coment; written in green we are supposed to read "but all 4 elements get printed separately without problem" as seen in my video. Without, not with! Sorry for the typo.

Thanks a lot for the precious help. I'll give my best to try to understand the answers and report back if I'm stucked. I didn't know unpack cannot accept 4 values.
What I find confusing is the fact that all 4 values are printed without issue separately before unpack.

Here resumed as a picture if easier to understand:

I hope someone will be able to help. I have an array with 4 elements coming from Arduino. I see each one without issue via [print] method after [fudiparse] (or after [cyclone/fromsymbol] if I use a different method), but I only see the first 2 when I unpack them!
In despite of spending hours trying different methods, I cannot get this to work in 1:44 min video: