Picked up a couple of red LED's and popped one in. Looks much better. Thanks UFN.
I noted a 60 Hz hum with low impedance headphones with the music off and the volume turned all the way up. Can't hear it with high impedance phones though. The cables hooked up to the RCA input are 2 conductor, shielded, and I had grounded the shielding. When I disconnected the shield ground, the hum went away. I had also grounded the output cables, but disconnecting those did not make a difference. For symmetry, I cut off all the ground wires to the shields.