With the patched kernel provided in comment #3, the issue is resolved. Pluging and unplugging the gigaset works fine, as well as lsusb, as well as hibernate/supsend. Thank you very much for your ultrafast helpful feedback.
With the patched kernel provided in comment #3, the issue is resolved. Pluging and unplugging the gigaset works fine, as well as lsusb, as well as hibernate/supsend. Thank you very much for your ultrafast helpful feedback.