Channel A, Current Offset on 2636B

Channel A has a +22.3uA offset in open circuit. Channel B has a <0.1pA reading in open circuit. Sources are set to zero. The channel A offset persists when connected to a 6220 precision current source while Channel B reads the same as the current source. I tried a factory reset, but that didn't change anything.

Unfortunately it sounds like you'll need to send the instrument in for repair. Request an RMA here: https://www.tek.com/en/services/repair/rma-request