Sonoff M5-1C incorectly shows 4 switches instead of 1

[wareczek]

Sonoff M5-1C: https://sonoff.tech/product/smart-wall-switches/m5/

This device has only 1 switch but after synchronization it shows 4 of them:

Info from diagnostics:

      "1001ec0623": {
        "uiid": 160,
        "params": {
          "bindInfos": "***",
          "version": 7,
          "switches": [
            {
              "switch": "off",
              "outlet": 0
            },
            {
              "switch": "off",
              "outlet": 1
            },
            {
              "switch": "off",
              "outlet": 2
            },
            {
              "switch": "off",
              "outlet": 3
            }
          ],
          "configure": [
            {
              "startup": "off",
              "outlet": 0
            },
            {
              "startup": "off",
              "outlet": 1
            },
            {
              "startup": "off",
              "outlet": 2
            },
            {
              "startup": "off",
              "outlet": 3
            }
          ],
          "pulses": [
            {
              "pulse": "off",
              "switch": "off",
              "width": 500,
              "outlet": 0
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 0,
              "outlet": 1
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 0,
              "outlet": 2
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 0,
              "outlet": 3
            }
          ],
          "sledOnline": "off",
          "staMac": "***",
          "rssi": -63,
          "offBrightness": 10,
          "fwVersion": "1.2.3",
          "only_device": {
            "ota": "success",
            "ota_fail_reason": 0
          }
        },
        "model": "M5-1C",
        "online": true,
        "local": true,
        "localtype": "plug",
        "host": "192.168.0.53:8081"
      }

I have M5-3C (3 switches) and shows properly with 3 controls:

It's diagnostics info:

      "1001f2749c": {
        "uiid": 162,
        "params": {
          "bindInfos": "***",
          "version": 7,
          "switches": [
            {
              "switch": "off",
              "outlet": 0
            },
            {
              "switch": "off",
              "outlet": 1
            },
            {
              "switch": "off",
              "outlet": 2
            },
            {
              "switch": "off",
              "outlet": 3
            }
          ],
          "configure": [
            {
              "startup": "off",
              "outlet": 0
            },
            {
              "startup": "off",
              "outlet": 1
            },
            {
              "startup": "off",
              "outlet": 2
            },
            {
              "startup": "off",
              "outlet": 3
            }
          ],
          "pulses": [
            {
              "pulse": "off",
              "switch": "off",
              "width": 500,
              "outlet": 0
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 500,
              "outlet": 1
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 500,
              "outlet": 2
            },
            {
              "pulse": "off",
              "switch": "off",
              "width": 0,
              "outlet": 3
            }
          ],
          "sledOnline": "off",
          "staMac": "***",
          "rssi": -44,
          "offBrightness": 10,
          "fwVersion": "1.2.3",
          "only_device": {
            "ota": "success",
            "ota_fail_reason": 0
          }
        },
        "model": "M5-3C",
        "online": true,
        "local": true,
        "localtype": "plug",
        "host": "192.168.0.180:8081"
      },