Hello, does anyone use the object [pd~] to successfully create sub-processes?

I have a patch running on a headless raspberry pi 3.
Now I want to move parts from the patch to subprocesses to move cpu load to another core.

The main-patch runs perfectly and I get all the output via ssh terminal.
After activating dsp in the main patch I start a sub-process, as described in the [pd~] help patch.
For testing, I print something with a [loadbang], which appears on the terminal,
but then it just seems to stop.
The process is still there, running and consuming cpu time, but a second, delayed print after the initial loadbang wont appear. An [osc~440] object also won't be hearable.

Now I'm wondering if it's a problem with the [pd~] object?
It prints "pd~ version 0.3" when the sub-process is started.

"puredata -version" prints "Pd-0.46.2 ("") compiled 07:48:11 Oct 29 2014"

Many greetings!