ITunes no longer streams smoothly to Apple TV

Question

Hi, folks. Have used my Apple TV for months with no problems whatsoever. I have primarily streamed iTunes music from a large library on an old G4 desktop. Streaming has always been rock solid.
But now I've upgraded my network to include a new Airport Extreme in the place of an old Airport Express, and my iTunes won't stream smoothly from the G4, no matter how I change my configurations. It feels like it simply can't keep up, which was never a problem before.
Music still streams very well from my (much smaller) library on my (much newer) laptop. But when coming from the G4, the stream will suddenly choke up without warning, or possibly with a hiccup, and then the screen will revert to the album menu rather than the track playing.
Any ideas how to fix? It's killing me that I've somehow lost this capability. The only factors that changed are the introduction of a new (better, faster) base station and the iTunes upgrade to 7.3, which I suspect may bog my G4 down in a way that it wasn't previously.

Answer 1

Updating to both 7.3 and 7.3.1 should have rebuilt
your library when you first opened itunes after the
update, given you have such a large library, I
suspect this should have taken some time and I
thought you would have noticed it.
The library did update in that way. But by "rebuilt," I guess I meant start from scratch. I feel that this particular library file has been building upon itself for years. Yes, it's constantly being overwritten, but not "rebuilt." I guess I'm not entirely sure what I meant.
On another point you mention about the time taken to
re-write ID tags, it may not be the reason in your
case, but the time this can take varies on the file
format
It's not necessarily the changing that's taking a long time... sometimes just accessing takes a long time.
That's all moot, really. The bottom line is that my G4 can't seem to stream its iTunes library to an Apple TV without dropping the stream. It doesn't happen when it's loading the library, it doesn't happen at any particular spike in network activity... it just arbitrarily lets go in the middle of the song, most of the time when streaming that song is all that the entirety of the network is doing.
I have tried changing Ethernet cables, changing base stations, defragmenting drives, altering transmit power, changing channels, changing multicast rates, clearing memory, etc. and the problem has been 100% consistent and completely unaffected by every variable. And the network works brilliantly when streaming from other, newer sources. I am so frustrated that I'm about to throw the Apple TV out the window. But I appreciate how hard you've tried to help. Cheers.