This light pattern indicates an error. You can look up these errors in Appendix F of the LSR User's Manual.

This particular error is MUTE, which is caused when the speaker is muted by pressing either the individual or system Mute button (in the LSR4300 Control Center software), or when SOLO is activated on another speaker.

To remedy this, un-mute the individual speaker or system mute, or exit SOLO on the other speaker(s).