Hi, we got a bunch of dlt's, 20 in total. We removed a lot of working reflection range inputs and replaced them with the dlt's. 4 of the dlt's when scanning in toolkit list the unit, gives it a network adress and under serial number it just goes ................ . Then it says the unit is not compatable with this version of C-bus Toolkit. Under firmware it says 3 where the other (working) units is 2.1.00. I am not on site my self but trying to remotly help one of our technicians. He also mentioned that the sticker with the serial number is pink on 4 trouble units and not white like we are acustemed to., Dont know if this has anything to do with it but i thought i'll mention it. Also we are using the latest toolkit 1.11 and also tried on 2 earlier versions. same result. Any Ideas?