FTPS uploads (using Filezilla) don't work

Command:    STOR 21120301.MP3
Response:    150 Opening BINARY mode data connection for file transfer.
Error:    GnuTLS error -15 in gnutls_record_recv: An unexpected TLS packet was received.
Error:    Could not read from socket: ECONNABORTED - Connection aborted
Error:    Disconnected from server
Error:    File transfer failed after transferring 151,635,342 bytes in 59 seconds

or, as reported by Jas Hud:

Command:STOR bbsfiles.dotcom.siterip.zip
Response:150 Opening BINARY mode data connection for file transfer.
Error:Connection timed out after 20 seconds of inactivity
Error:File transfer failed