Hello Rex Alex,
I don’t know which Data was in snd_buffer. On my console I got data like smilees and hearts etc 
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The problem was a wrong pointer to data hand over.
I wrote snd_buffer= ptrbuff but the correct line is snd_buffer=&buff_1 because my data is in buf_1 and ptrbuff is only a pointer to the data.
Now I have corrected the line and everything works fine 