Please ensure your WiFi speakers are all connected to the 2.4Ghz network.
If you have lots of devices running on your router this can cause congestion which then can cause all kinds of issues.
It’s worth checking how many devices are connected ; ie phones, TVs, laptops, thermostats etc as your router may be hitting the workable limit for the number of IP addresses it can simultaneously handle at any given time.
When connecting Lithe Audio speakers to a Mesh Wi-Fi Router or Access point(s), we recommend connecting all the WiFi speakers you want to group to a single node at this time.
This will ensure your phone or device can see all discoverable speakers on the Lithe audio App and play to multiple zones together or as single zone, without latency or loss of sound.