can't run multiple streams on Windows 2008 x64

[digitalsystem]

Hi WinAmp forums...long time lurker, first time poster

We used to have a physical Windows 2003 server running two instances of Shoutcast, and two locally-encoded streams (one high-bandwidth, one low-bandwidth). Our school IT folks wanted to take over the server function. So we now have a Windows XP box encoding our two streams with the latest WinAmp and the 2.11 DSP plugin, which are then sent to a virtual Windows 2008 x64 Shoutcast server in our school's data center. The DSP plugin is set for 1.x legacy mode. The high-bandwidth stream runs like a champ. However, the low-bandwidth stream does not work because the encoder can't connect to the server. There are no firewalls in the way. Netstat tells me that the port on the server is listening, and telnet tests to the port are successful. But the server will not respond to the encoder, and when I connect to the status page it says the server is down. Both SrcIP and DstIP are set to ANY. I did try getting another virtual IP and setting DestIP to separate addresses for each stream, but no luck with that. I also tried running just the low-bandwidth stream without the high-bandwidth stream, but it made no difference.

Here's what the high-bandwidth stream looks like:
PortBase = 8000
Status page - server is up and source is listed as our encoder's IP
Admin page - Incoming interface: encoder_ip:8001 - Outgoing interface: ANY:8000
The log looks normal.

And here's the low-bandwidth stream:
PortBase = 8002
Status page - server is currently down
Admin page - Incoming interface ANY:8003 - Outgoing interface: ANY:8002

Log for low-bandwidth stream:
<01/31/11@18:23:22> [SHOUTcast] DNAS/win32 v1.9.8 (Feb 28 2007) starting up...
<01/31/11@18:23:22> [main] loaded config from D:\Program Files\Shoutcast\sc_serv.ini
<01/31/11@18:23:22> [main] initializing (usermax:200 portbase:8002)...
<01/31/11@18:23:22> [main] No ban file found (sc_serv.ban)
<01/31/11@18:23:22> [main] No rip file found (sc_serv.rip)
<01/31/11@18:23:22> [main] opening source socket
<01/31/11@18:23:22> [main] source thread starting
<01/31/11@18:23:22> [main] opening client socket
<01/31/11@18:23:22> [main] Client Stream thread [0] starting
<01/31/11@18:23:22> [main] client main thread starting
<01/31/11@18:23:22> [source] listening for connection on port 8003
<01/31/11@19:13:53> [dest: random_ip] server unavailable, disconnecting
<01/31/11@19:15:53> [dest: random_ip2] server unavailable, disconnecting
<01/31/11@19:19:53> [dest: random_ip3] server unavailable, disconnecting
…lots more IPs

I saw a thread here which looked kind of similar, so I checked to see if IPSec was an issue. However, there are no active IPSec rules on this server. So, does anyone else have any suggestions?