Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems 861v8 - Bad Code Combination

You might also want to try reseating the cards and/or use a contact cleaner spray on the card slots (and repeatedly, and gently, insert/remove the cards to dislodge gunk and oxidation).

Edit: in an 861v4, it's often a bad contact on the DSP CD/EF cards which can cause this error. These cards are a bit further in than the I/O cards, but I don't think you need to remove the case (though you might). If you attempt to remove the case, don't remove the screws of death!