Home Sharing not working as expected.
I can browse all of the laptop media and play it without any issue when I'm on the desktop machine, but when I try to access the desktop's library from the laptop the home sharing doesn't appear in the iTunes shared area.
I've tried disabling home sharing and re-enabling (many, many times) and all this has done is to cause the home sharing to (occasionally) re-appear on the laptop for a few minutes. If I'm quick enough and click on it before it disappears I can establish a connection. As long as I keep streaming content all is well, but if I let it go idle for even a few minutes, I'm back to square one, and the sharing disappears.
Even stranger; even though the shared library has disappeared from iTunes on the laptop, it often reappears after about ten or fifteen minutes, but I'm still unable to connect to it. Clicking causes it to disappear again.
I have also disabled all firewall software on the desktop and laptop to eliminate that as a cause for the problem.
Finally, no matter what state the shared library is in on the laptop (hidden, connected, showing), it has no effect on being able to access the laptop's media from the desktop. Also, the problem seems to be worse when I'm using the laptop wirelessly. That is to say, the desktop shared library disappears quicker, or doesn't show up at all, when I'm wireless.
I'm out of ideas on how to fix this, and I'd appreciate any suggestions.
Added more details
MacBook Pro, Mac OS X (10.6.4)