Help with iTunes library failure after SnowLeopard

I have three Mac Minis that play to DACs on three separate systems. Things have been great until a week ago.

One Mac Mini has the library on a separate, USB-connected hard drive.

This is “home base[HB]”, and until recently the two other Mac Mini systems (out-boards [OBs] downloaded the library stored on the HB library and played from that library just fine.

I installed Snowleopard on all three Mac Minis. All went well with that. Until a week ago, the two other Mac Mini OBs loaded the library just fine from the HB computer library. Both OB computers loaded the library and played just fine.

Now, nothing doing.

Each of the two OBs seeks the library on the HB computer. When this happens, the library is never loaded on the seeking OB computer, and the library loading process causes the whirling disc syndrome (cursor) on the HB computer causing (eventually) a forced shutdown of iTunes on that computer.

The library names haven’t changed. The sharing settings haven’t changed. The library fails to load onto the two other “outboard” computers.

The wireless is working fine (loads Safari just fine, loads Netflix just fine for streaming movies, likewise Rhaposdy).

I am truly puzzled.

Your thoughtful assistance is much appreciated.

:) listening,

Ed