There was another thread about best dosing pumps that seemed to bore into a discussion about the plum xl3 infusion pump. Just got one and had some questions and wanted to start a new thread. Got mine from eBay from a seller that said he tested you're quipment before sending. When I got mine I played around in the First Bank and thought I had to set Prime properly but kept getting error message. Played around with this nd that let it syphon through the line for a while. Kept tapping bubbles out. Finally walked away came back still had problems. Put the cassette in the middle bank and had no problems. Pumped like a champ. Let it run for a while no problems. Went back to bank A to see if maybe there bubbles cleared and got the occlusion error message again. Decided to try Banks C and got the same error messages. My question is, are some banks just more sensitive than others. Or did this being a technical problem that I need to exchange the pump.