6545 QTOF with noise at low mass and bad response at high mass

Hello, hoping the collective Agilent community wisdom has ideas about what to try next. We have a 6545 QTOF that has been giving us the response in the attached photo. We have tried everything we can think of to get back to what a good tune solution should look like including:

- solution made with a newly purchased bottle of ESI-L, new ampule of biopolymer mix, newly opened bottles of Fisher Optima LC-MS acetonitrile and Fisher Optima LC-MS water

- flushed tubing between the bottle and the nebulizer with acetonitrile/water, flushed nebulizer and cleaned and inspected nebulizer and the spray looks good. We see the same spectrum with the tune solution coming from the top nebulizer on the jet stream source and the reference nebulizer

- vacuum looks normal, ion transfer capillary has been freshly cleaned, source has been freshly cleaned

And now we are stumped. We would be grateful for any ideas.

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