rule = {
    matches = {
        {
            { "node.name", "equals", "alsa_input.pci-0000_07_00.6.HiFi__hw_Generic_1__source" },
        },
    },
    apply_properties = {
        ["node.description"] = "Laptop Headphones Microphone",
        ["node.nick"] = "laptop-headphones-mic",
    },
}

table.insert(alsa_monitor.rules, rule)