solved!
#AGENT_EXTRA_OPTIONS_X="-nolisten tcp" # is commented out!!
AGENT_EXTRA_OPTIONS_X=""is the solution! That deletes the default X argument, although its commented out in standard node.conf!!
Thanks to Michael from Vienna: https://urldefense.proofpoint.com/v2/url?u=https-3A__debianforum.de_forum_viewtopic.php-3Fp-3D1287341-23p1287341&d=DwIDaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=gd8BzeSQcySVxr0gDWSEbN-P-pgDXkdyCtaMqdCgPPdW1cyL5RIpaIYrCn8C5x2A&m=POgzcxww4EXaBUxpzNuo2GnmXZiDJtohNE7L5yNti-9hWCRA2FoWrahmMKjk4xGH&s=bOubfrGfUmhhO-HMRzH-MfSTc-bprxFvZ3ViYimyXT4&e=
Thank you for all here who helped me!!! :) Eckard
