Strange Noise | Fronius Symo

Some have managed to stop the ticking noise by cycling the inverter off/wait/on, but others not so lucky. There seems to be at least 2 noise issues after this update - this new ticking sound and a different whine to the usual occasional fan noise. Some have mentioned the noise is only obvious or worse at around 50% PV generation.

Hi. I have since power-cycled my Fronius inverter. Despite cross my fingers the noise hasn’t gone away. I’ve heard at several intervals. There’s no obvious pattern to the noise occurring other than the inverter is actually inverting at the time ( I have not heard any strange noise(s) after dark - I am also less likely to be outside too ). The temperature here in Perth has been quite mild. I do log the Inverter Temp too. The inverter fan noise has been fairly low as compared to the middle of summer on a 40C day. All very odd.

All. I have an update. After contacting the installer, who didn’t really want to know, I contacted Fronius directly. After some mucking around trying to send them the audio files they ( Fronius ) have advised me that they have escalated the problem.

I noticed yesterday ( PM ) that my inverter’s firmware was being changed - not by me. The firmware has been rolled back to fro32071.upd

The strange noise that I originally reported had continued off an on up until the point that the firmware was altered. I have not heard the noise since the firmware downgrade but it’s still a bit too early to be sure.

Stay tuned.



Fronius confirmed that they rolled back my inverter’s firmware to the previous version fro32071 from version fro32370. They also stated that the newer version was responsible for the odd sound in some instances.

Since the firmware was rolled back I have not heard any odd noise(s) coming from the inverter.


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Good to hear (boom-tish!) you got a rectified outcome from the supplier.

I know that sound, its the Londen metro at Trafalgar Square


In the continuing saga. Fronius have released fro32410.upd of the firmware. This versions supersedes the troubled version ( see above ). After checking with Fronius that it would be ‘safe’ to update my inverter from fro32071 I went ahead and did so.

Alas the strange noise has returned although it sounds slightly different to before. It still sounds like distressed electronic components. I have advised Fronius of the problem and provided them with an mp3 recording of the noise.

Stay tuned.


Following my email to Fronius and supplying them with a newer mp3 recording they have [ remotely ] changed the inverter’s firmware from fro32410.upd to dcr32420.upd [ Yes dcr32420.upd ]. The strange noise has disappeared - again.


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Another update.

This morning I walked by my inverter and could hear that the weird / strange noise had returned. I have recorded the sound on my phone. Before emailing Fronius I checked the version of the firmware in the inverter. I found that it had been updated late last night ( WST ) from dcr32420.upd to fro32450.upd.

I will let you know what Fronius have to say about the matter.


Thanks for the reminder for me to go to my inverter settings and set “Allow automatic updates” to off!


The update to fro32450.upd [ The latest update as of the time of writing this ] has caused the same noise problem. Fronius have rolled the firmware back to fro32071.upd

Not making much headway here!


My Symo is still on fro31331.upd

Re the Primo 3kW
Same issue here with the odd noise it sound like one of the high frequency coil transformers has changed freqency ?
New update 482 is availble for updating now.
Will report if fixed the issue?
Only started when it had an update sometime back.

Hi. Fronius upgraded the firmware of my inverter to fro32482.upd on 06DEC2021. I am happy to report that so far so good - I have not heard any odd noises coming from my inverter.

However it has been extremely hot here so I haven’t been outside as much as normal and the inverter fans have been very loud and would tend to mask any underlying noise.

We are experiencing milder weather now, thank goodness so it will be easier to hear if anything happens. If I don’t hear any weird noised in the next few days I’ll assume that the problem has been finally fixed.


Since my inverter was updated to fro32482.upd I have had no further issues.


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any reason to keep updating them?
I haven’t updated mine forever.

Some of the changes relate to the inverter being connected to other ‘grids’ so aren’t really relevant to me whereas some updates do affect performance - Fronius adjust some of the internal parameters of the inverter.

Updates to the Datamanager card are probably more important and may plug security holes.

It has been confirmed by Fronius that 32482 can create other problems - e.g. total generation losses by approximate 50% especially at bad weather/low light conditions (MPP Tracker problems).
There is also a thread about this in the German PV-Forum/Fronius.

The current workaround to fix this is to contact the fronius support and to request a downgrade to 32071. My configuration is a Symo 20 and 5 and a Fronius Smartmeter.

Updating the datamanager to Version 3.19.10-1 resulted for all OpenWB Wallbox users and me to the error, that now the day production is not anymore tracked/recorded. Unfortunately there is no way to downgrade the Datamanger, so OpenWB users have to wait for a fix by OpenWB now :frowning:

Hi @lemuba,

Thanks for the information. I wonder what on earth is going on at Fronius HQ! They seem to be suffering from a few quality control measures lately.

I haven’t observed any loss of production since the update but the weather conditions here ( Perth, Western Australia ) have been very good [ apart from the unpleasant heat ] so the only low-light is essentially sunrise and sunset.

The Datamanager release notes mention a ‘Bugfix’ to the Modbus API. I wonder if Fronius have also introduced a bug!

Software Version: V3.19.10-1

/ Remote control option for electric utility companies
/ New firmware V36 for UL Meter is supported
/ Phase accurate feed-in limit possible (weakest phase approach)

> / Modbus API: Status Fault only occurs when the inverter is not feeding into the grid
/ The management of older devices (IG,…) has been improved


I have uploaded yesterday’s production vs the day before my inverter’s firmware was updated to fro32482

There is little difference between the two days. Yesterday was a bit closer to the southern summer solstice.

05DEC2021 was 32.3C [ MAX ] with 13.1 hours of daylight.

02JAN2022 was 32.4C [ MAX ] with 13.2 hours of daylight.