Just changed to a HP Pentium 4 3Gig XP Pro running the latest stable version of Pico 6. I don't now why but all channels sit on 300mV and will not zero. I tried a 1.6V supply on all the channels. Firstly in the correct polarity but the trace dropped to 200mV. I reversed the supply which read the correct -1.6V.
Should I be suspicious of the PC ?