I have a Burnham Alpine 105 w/ Sage 2.1 that won't begin throttling back until 5F or more above the setpoint (and takes its time once it does start, so the supply temp rises even further). This happens for DHW and central heat demand, regardless of the setpoint. The control board has been replaced but it hasn't changed this behavior.

For now we've been tweaking the diff above/below and max modulation rate to try to reduce cycling, but any ideas or suggestions as to what may be causing this?