More on QuickTime 7.1.5
The issue caused by QuickTime 7.1.5 on Mac OS X 10.3.9 persists. The only workaround I have found to date is to downgrade QuickTime back to version 7.1.3. There is a thread on Apple’s discussion board that describes how to do this.
Although this procedure appears on Apple’s discussion board, it is not necessarily something Apple (or Yellow Mug!) endorses. So if you choose to downgrade, please back up your hard drive first and do so at your own risks.