I have same problem. When i download file from rapidgator with a premium account in JDownloader on Windows 10, the speed will drop from >2MiB/s down to 100KiB/s. And then slows to a stop, connection probablems. Only in Edge and the speed stable at 1.5MiB/s.

29.09.17 21.52.06 <--> 29.09.17 22.12.02 jdlog://0926614015941/
28.09.17 21.16.23 <--> 28.09.17 21.16.23 jdlog://5665614015941/