PS for the 8 zone (I think it also works on Audio matrices as well): https://www.ebay.com/itm/AUDIO-PSU-ALP0800-Audio-Line-Switch-Mode-Power-Supply-960W-Continuous-/111004308644?hash=item19d85f54a4:g:DCUAAOSwcBhWXNVc
I have no clue what is the part number for the 4 zone. Can't find any info about it...