Full local control of Marshall Woburn/Stanmore (Frontier Silicon / FSAPI) via WiFi — finally!

After years of the Marshall multiroom speakers being a smart-home dead end, I’m happy to report that full local control over WiFi is possible using Home Assistant’s built-in frontier_silicon integration — no cloud, no companion app, no HACS custom component required.

Some history first

This isn’t a brand new discovery, but it seems to have stayed scattered and never quite converged into a clear solution:

My setup is different: I’m using the WiFi/network interface, not Bluetooth, and controlling a Marshall Woburn (original/full version). I don’t own a Stanmore 2 or other models, so I can’t confirm this works identically across the whole Marshall lineup — but if you have a different model with a Frontier Silicon chipset, it’s very likely worth testing the same approach before assuming it’s not supported.

What I found

The Woburn/Stanmore (full versions) are built on a Frontier Silicon chipset, which exposes a local HTTP control protocol called FSAPI. It’s under-documented but fully functional — power, volume, input source, and EQ presets are all controllable over plain HTTP on the local network.

Home Assistant already ships a native integration, frontier_silicon, that handles all of this out of the box:

  • Settings → Devices & Services → Add Integration → Frontier Silicon
  • Host: your speaker’s local IP address
  • Port: 80

That’s it — no session management to worry about, HA handles it internally. Power, source selection, and volume showed up immediately as controllable entities.

Why this matters

Both linked threads show people have wanted this for at least 5 years, generally assuming Marshall/Zound Industries would either never respond or that it was a Bluetooth-only story. Since these speakers apparently all share the same Frontier Silicon foundation, it seems reasonable to expect the WiFi/FSAPI approach could work on other Marshall multiroom models too (Acton, Kilburn, Stanmore 2/3, etc.) — but again, unconfirmed by me, so if you try it on a different model, please report back here!

Happy to answer questions or share the exact FSAPI calls I used if anyone wants to explore further before the integration handles everything automatically.

Hey thanks for sharing, my Stanmore II didn’t have Wifi, would this still work?

Hey Aaron,

From what I saw, the protocol used for this is http (port 80) so if your device does not have http capabilities, it seems pretty difficult to apply the same approach.

Hello CPAeby,

As the first one being annoyed by the lack of cooperation of Zound Industries, I can happily declare that the HA frontier integration works for my Stanmore II . This is a great achievement and I would like to commend the developer(s) for making this possible. It has been a PITA ever since I bought the speaker. Thank you very much.

Thank you @elonden for your return! Your initial message was the motivator for me to find a solution. I was ready to reverse engineer the android app to find how to act directly on the speaker! But it was easier than I thought thank to the integration.

I’m glad it helped!

See you!