FTP connection problem Mac Book Pro retina

I have a new MAcBook Pro with Retina display. I also use a Thundebolt - Ethernet connection for FTP.

On my old Windows lap top I used FileZilla to connect with a HD receiver - recorder to transfer files from the recorder to the computer. (Humax iHDR 550C receiver – recorder with hard disk)

What ever I try on my Mac, I can get no connection with the recorder. I have shut down WiFi, shut down the Firewall, used another Thunderbolt port, used FileZilla for Mac and tried several other programs. Nothing seems to work. I always get the message "connection lost"

As I performed a test, all tests are working, untill the dataconnection. There seems to be a failure on the data connection. Has is something to do with "Thunderbolt to Ehternet" cable? (If I plug in the Thunderbolt cable I see litte "sparks" if I touch the metal housing of the Mac).

This morning I tried it again with my old Windows lap top, it connected within a second.

Can someone help me with this problem?

Hans.