Optical audio output cuts out
I have a PowerMac G5 Dual 2.7GHz and running 10.4.9. I need to get digital audio from my G5 to my theater in another room. I bought an optical-coaxial digital audio converter and used an optical cable and a 50ft coaxial digital audio cable to make the connection. Sound cuts out constantly about every second. I've tried playing material from Final Cut Pro, iTunes, Quicktime Pro, and Finder and get the same results so I know it's not any of those specific apps causing the problem. I have the latest versions of everything, OS, applications, and firmware.
I tested the optical-coaxial adapter, optical cable, and the 50ft coaxial digital audio cable on another source and it worked perfectly. Any idea how I can fix this? Is there a setting or preference somewhere or is it a hardware issue? Anyone else out there have this problem?
PowerMac G5 Dual 2.7GHz, Mac OS X (10.4.9), 30" HD Cinema Display