I doubt anyone has a hotline into the serial number database, but if these follow convention, the D8k2 would imply a second revision, the 150 would be a 150'th pair and the A being A of an AB pair.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).