Newer Devices Slower To Respond to LAN Messages

Hello! I have several Lifx lights in my apartment. I have one A19 bulb that I bought a while ago that is on firmware v2.90. The others are all newer and on firmware v3.90.

The older A19 bulb always responds quickly to broadcast discovery UDP packets, but it’s hit-or-miss if the others do. Why is this?

EDIT: I know there’s probably a lot of other factors, but firmware is the one thing I noticed. Perhaps there’s other factors that are actually the cause.

EDIT 2: Pinging the other lights also results in wildly varying ping times and packet loss while the A19 has consistent ping times.