Thanks for reaching out and I'm sorry to hear that you're having issues with your Google Wifi. I'd love to know more about this and I have a few questions:
Looking forward to your response.
I have no idea what firmware is. My provider provides 1 GIg speed. Mine is around 100mbs upload and download. There are times the speed is in single digits. On my google ap, it indicates a 750 plus speed coming from provider.
Thanks for the response. Wi-Fi speed can vary depending on a few things: the type of device you are using, distance between the device and your router or point, the frequency your devices are connected to, and physical barriers like walls in your home.
If you haven't yet, please try the troubleshooting steps on this link to isolate the issue.