I've installed QT 4, but have yet to successfully try the streaming feature. Every time, the player window comes up, and just when it looks like it is going to start playing, my system crashes to what looks like a debugger. The following error message is displayed:
GetConfigurationMethodFromIITF: Did not consume correct number of bytes
The same problem occurs when attempting with video or audio.
I am using one of the early G3 MT's, 266MHz, 128MB RAM, Netscape 4.5, 56k modem, and OS 8.1. I've tried disabling most of the extensions not related to QT or getting online, to no effect. Any suggestions would be appreciated.

Update: I've found that if I disable MacsBug, the symptoms change. When I first access a page with streaming content, and QT 4 trys to display the feed, Navigator quits with a Error Type 12 and the computer recommends closing open Apps and restarting. If instead I restart Navigator and again try to access the same page, now I can properly receive the streaming video or audio!

The problem is gone!

I updated to version 4.0b22 and my system no longer crashes.