Skyconnect multiprotocol makes Zigbee extremely unreliable

I’ve enabled multi pan on my skyconnect stick that has run zigbee since January. Adding matter devices worked (after the second attempt!) and i can control stuff via matter. But all zigbee lights in ZHA react either delayed, not at all or to every other request. Did anyone else run into it? As soon as i go back to the zigbee only version everything works as expected again (well… besides matter devices that is).

Were Zigbee and Thread on the same channel ?

yes, both ran on channel 15. I didn’t try to move it though. This hasn’t been the first time. Even without any matter devices this has been the case for me.

Highly recommend that you start by following this to rule out both interference and lack of routers → Guide for Zigbee interference avoidance and network range/coverage optimization (weird symptoms are usually due to EMF interference from something so before doing anything else start by connecting the Zigbee Coordinator via a very long USB extension cable to get it far way from other devices, and be sure to only connect to to a USB 2.0 port, so connect it via a powered USB 2.0 hub if your computer only have USB 3.x ports. Know that USB 3.x ports and USB 3.x devices will cause serious EMF interference for Zigbee).

If that does not work then also consider upgrading the Zigbee Coordinator firmware to a later version.

I’m running it via long cable and USB2.0 - as i mentioned above, it works perfectly fine with zigbee only. I was also under the impression that HA would update the firmware when necessary - or at least use the latest stable version if you switch over to the multi pan. This only happens as soon as i enable matter support. Shouldn’t EMF problems also arise with zigbee only, if it were the stick?
Your theory might be true, if both protocols interfered with each other?

Did you ever get this sorted? I just enabled multiprotocol and now zigbee is delayed or doesnt respond first time

I had multiprotocol working with zigbee for a while, but switched back to zigbee only. The purchase page reads (the last line is most important):

…we have concluded that while Silicon Labs’ multiprotocol works, it comes with technical limitations. These limitations mean users will not have the best experience compared to using dedicated Zigbee and Thread radios. That is why we do not recommend using this firmware, and it will remain an experimental feature of Home Assistant SkyConnect.

Again, the last line doesn’t give much hope: “…it will remain an experimental feature of Home Assistant SkyConnect.”

Does that mean the developers will someday return to this project and resolve those “technical limitations”? I have no idea. I bought mine before this disclaimer was added on the purchasing webpage, so I was disappointed. But that’s the nature of the business model and why it’s so inexpensive.

latest updates and a long usb 2.0 cable run helped out in the end for me. Matter and Zigbee work just fine now