Of course there is!
All you have to do is log on in to shell using putty or any other similar programm using root account (default l/p is root / welc0me) and then edit ftp daemons configuration file.
After you log on do this:
and change 1 line from this:
Of course you can use any other number you like. With 5 you will allow 5 connections from one IP.
After you made changes, save file.
And do this: