CH released firmware updates for C1, D1, T1, P1 and X1 during the week. These are largely to fix a few bugs but also to cater for a new display board as the old ones are no longer available to CH. These new firmware updates also fix a few labels that are not politically correct! Amazing! Can't say I can hear any difference in terms of SQ so no need to rush........ unless of course you have been offended by some of the words used in their menu....