Juno-Gi playing flat

[Blackcloud6]

My wife has a Juno-Gi and when practicing together her Juno plays flat. I'm playing guitar with Standard Tuning (440 hz) and checked the guitar's tuning with two different tuners set at 440. In order to play in tune, we have to set the Master Setting tuning on the Juno to 449 hz. Once we do that all is fine. Could she have inadvertently changed a setting or doing something to cause this? It seems very odd to me that a computer can go flat so something has to be set wrong.

We did download the latest update and installed in but the problem persisted.

Thnaks in advance for your help.