Salty and Xenon,

Many thanks for your replies.

Before I viewed and had a chance to act on either of your helpful suggestions, I had unplugged and "disassembled" everything and put then Humpty-Dumpty back together again.

For reasons that are unclear to me, everything is right with the world again, and I'm happily listening to Miles Davis's "Big Fun."

Happy listening to you both,

STeve