Please post a log.
Please post
your log-ID here | bitte poste
deine Log-ID hier.
As stated in the linked help article (sorry for the confusion with that "low speed" topic) - there are some possible solutions available but we need some more information about your CPU/Java version.
I will soon improve the linked help article and make one independant from "low speed issues" to make this less distracting!
-psp-
EDIT
The new support article is here:
https://support.jdownloader.org/Know...ng-downloading
Chances are very high that this is the cause of your issue --> Follow the instructions and try again with other / newer Java versions (see instructions in linked article).