here is the debug log when the problem appears, this is copied from xbmc.old.log
13:46:39 M: 45785088 INFO: Key combination detected for full debug logging (X+Y)
13:46:39 M: 45785088 NOTICE: Running the application...
13:46:39 M: 45785088 DEBUG: CApplication::OnMessage : Translating ReplaceWindow(Home)
13:46:39 M: 45785088 DEBUG: CApplication::OnMessage : To ReplaceWindow(Home)
13:46:39 M: 45785088 DEBUG: Activating window ID: 10000
13:46:39 M: 45785088 DEBUG: Checking if window ID 10000 is locked.
13:46:39 M: 44625920 DEBUG: FreeVisualisation() started
13:46:39 M: 44625920 DEBUG: FreeVisualisation() done
13:46:39 M: 40693760 INFO: CNetwork::LogState - Link: full duplex
13:46:39 M: 40693760 INFO: CNetwork::LogState - Link: 100 mbps
13:46:39 M: 40693760 INFO: CNetwork::LogState - State: dns
13:46:39 M: 40693760 INFO: CNetwork::LogState - State: static
13:46:39 M: 40693760 INFO: CNetwork::LogState - ip: 192.168.0.140
13:46:39 M: 40693760 INFO: CNetwork::LogState - subnet: 255.255.255.0
13:46:39 M: 40693760 INFO: CNetwork::LogState - gateway: 192.168.0.1
13:46:39 M: 40693760 INFO: CNetwork::LogState - dns: 192.168.0.1, 0.0.0.0
13:46:39 M: 40693760 DEBUG: CNetwork::NetworkMessage - Starting network services
13:46:39 M: 40693760 NOTICE: start timeserver client
13:46:39 M: 40169472 NOTICE: XBFileZilla: Starting...
13:46:39 M: 37535744 NOTICE: XBFileZilla: Started
13:46:44 M: 37216256 ERROR: Unable to wait for NTP reply from the SNTP server, GetLastError returns 10060
13:47:46 M: 37711872 INFO: CNetwork::LogState - State: dns
13:47:46 M: 37711872 INFO: CNetwork::LogState - State: static
13:47:46 M: 37711872 INFO: CNetwork::LogState - ip: 192.168.0.140
13:47:46 M: 37711872 INFO: CNetwork::LogState - subnet: 255.255.255.0
13:47:46 M: 37711872 INFO: CNetwork::LogState - gateway: 192.168.0.1
13:47:46 M: 37711872 INFO: CNetwork::LogState - dns: 192.168.0.1, 0.0.0.0
13:47:46 M: 37711872 DEBUG: CNetwork::NetworkMessage - Stopping network services
13:47:46 M: 37711872 NOTICE: stop time server client
13:47:46 M: 38236160 INFO: XBFileZilla: Stopping...
13:47:46 M: 39976960 INFO: XBFileZilla: Stopped
13:47:46 M: 39976960 DEBUG: CNetwork::NetworkMessage - Starting network services
13:47:46 M: 39976960 NOTICE: start timeserver client
13:47:46 M: 39452672 NOTICE: XBFileZilla: Starting...
13:47:46 M: 37875712 NOTICE: XBFileZilla: Started
13:47:48 M: 37130240 INFO: CNetwork::LogState - Link: full duplex
13:47:48 M: 37130240 INFO: CNetwork::LogState - Link: 100 mbps
13:47:48 M: 37130240 INFO: CNetwork::LogState - State: dns
13:47:48 M: 37130240 INFO: CNetwork::LogState - State: static
13:47:48 M: 37130240 INFO: CNetwork::LogState - ip: 192.168.0.140
13:47:48 M: 37130240 INFO: CNetwork::LogState - subnet: 255.255.255.0
13:47:48 M: 37130240 INFO: CNetwork::LogState - gateway: 192.168.0.1
13:47:48 M: 37130240 INFO: CNetwork::LogState - dns: 192.168.0.1, 0.0.0.0
13:47:48 M: 37130240 DEBUG: CNetwork::NetworkMessage - Stopping network services
13:47:48 M: 37130240 NOTICE: stop time server client
13:47:51 M: 37130240 ERROR: Unable to wait for NTP reply from the SNTP server, GetLastError returns 10060
13:47:52 M: 37654528 INFO: XBFileZilla: Stopping...
13:47:52 M: 39231488 INFO: XBFileZilla: Stopped
13:47:52 M: 39231488 DEBUG: CNetwork::NetworkMessage - Starting network services
13:47:52 M: 39231488 NOTICE: start timeserver client
13:47:52 M: 38707200 NOTICE: XBFileZilla: Starting...
13:47:52 M: 37875712 NOTICE: XBFileZilla: Started
13:47:57 M: 37875712 ERROR: Unable to wait for NTP reply from the SNTP server, GetLastError returns 10060
13:48:31 M: 37875712 DEBUG: Activating window ID: 10114
13:48:31 M: 37875712 DEBUG: Checking if window ID 10114 is locked.
13:48:31 M: 37875712 INFO: Loading skin file: PlayerControls.xml
And here is the flashfxp log V3 Build 1015
WinSock 2.0 -- OpenSSL 0.9.7d 17 Mar 2004
[R] Connecting to Xbox -> IP=192.168.0.140 PORT=21
[R] Connected to Xbox
[R] 220-Welcome to XBOX FileZilla (XBMC)
[R] 220-version: XBMC:FileZilla version 1.5.6, (based on FileZilla Server 0.8.8)
[R] 220
http://sourceforge.net/projects/xbfilezilla
[R] USER xbox
[R] 331 Password required for xbox
[R] PASS (hidden)
[R] 230 Logged on
[R] SYST
[R] 215 UNIX emulated by FileZilla
[R] FEAT
[R] 500 Syntax error, command unrecognized.
[R] REST 100
[R] 350 Rest supported. Restarting at 100
[R] REST 0
[R] 350 Rest supported. Restarting at 0
[R] PWD
[R] 257 "/" is current directory.
[R] TYPE A
[R] 200 Type set to A
[R] PORT 192,168,0,100,8,88
[R] 200 Port command successful
[R] LIST -al
[R] 150 Opening data channel for directory list.
[R] 226- Free space: [C:\ 317.19 MB] [E:\ 4.20 GB] [F:\ 70.58 GB] [G:\ 0.00 bytes]
[R] 226 Transfer OK
[R] List Complete: 224 bytes in 0,03 seconds (7,1 KB/s)
[R] CWD F
[R] 250 CWD successful. "/F" is current directory.
[R] PWD
[R] 257 "/F" is current directory.
[R] TYPE A
[R] 200 Type set to A
[R] PORT 192,168,0,100,8,89
[R] 200 Port command successful
[R] LIST -al
[R] 150 Opening data channel for directory list.
[R] 226- Free space: [C:\ 317.19 MB] [E:\ 4.20 GB] [F:\ 70.58 GB] [G:\ 0.00 bytes]
[R] 226 Transfer OK
[R] List Complete: 1 KB in 0,13 seconds (9,4 KB/s)
[R] TYPE I
[R] 200 Type set to I
[R] PORT 192,168,0,100,8,90
[R] 200 Port command successful
[R] STOR Nya hyss av Emil i Lönneberga.avi
[R] 150 Opening data channel for file transfer.
[R] 421 Kicked by Administrator
[R] Transfer Failed!
[R] Connection lost: Xbox
[R] Attempting to Reconnect.
[R] Connecting to Xbox -> IP=192.168.0.140 PORT=21 (attempt # 1)
[R] Connection failed (Connection refused)
[R] Delaying for 120 seconds before reconnect attempt #2