I have a DSP5000C with firmware v4.003. Can anybody tell me what firmware v5.04 adds, and more importantly, how does one update firmware on speakers. Thanks.

Also, my 506, the 18-bit version with the newer transport and serial numbers beginning with 2xxxxx, has software version 1.12.

FYI, there are two firmware versions for the 551. As I recall, they changed an internal part which required an update to the firmware, so if you have a 551 with a different version that 2.4, your firmware may be the latest for your 551. Check with Meridian to be sure.

561, DSP5500s, DSP5000C, analog sides and rears