To anyone with a Fronius Primo inverter.....

Have you ever heard it making odd squeaky noises, as it starts up in the morning? I noticed one morning that we were not showing any solar on the app. (with a reasonably bright sky), so I went to look at the inverter in the garage. It was making the odd noise, which was changing in pitch/tone, and could even have been an alarm sound, if it was louder. It was nothing like fan noise. I am not sure what the screen was showing at this time. Soon after this it stropped the noise, and started to show solar generation in the app.

(We do not have the comms. card in our inverter, so no ability to monitor remotely)

Any thoughts or observations from other Primo owners?