diff --git a/custom_components/xiaomi_gateway3/core/devices.py b/custom_components/xiaomi_gateway3/core/devices.py
index c9f6ba2b..5a5aff65 100644
--- a/custom_components/xiaomi_gateway3/core/devices.py
+++ b/custom_components/xiaomi_gateway3/core/devices.py
@@ -1508,7 +1508,7 @@
         BLEMathConv("illuminance", "sensor", mi=15),  # moving with illuminance data
         BLEMathConv("illuminance", mi=4103),  # uint24
         BLEBattery2691("battery", "sensor", mi=4106, entity=ENTITY_LAZY),  # battery data with bug
-        BaseConv("idle_time", "sensor", mi=4119),  # diagnostic
+        BLEMathConv("idle_time", "sensor", mi=4119),  # diagnostic
         BLEMapConv("light", "binary_sensor", mi=4120, map={"00": False, "01": True}),
     ],
     # "ttl": "60m",  # battery every 11 min
diff --git a/tests/test_conv_ble.py b/tests/test_conv_ble.py
index 847aa295..0eed6c48 100644
--- a/tests/test_conv_ble.py
+++ b/tests/test_conv_ble.py
@@ -367,3 +367,10 @@ def test_18051():
     assert p == {"occupancy": True}
     p = device.decode({"eid": 18513, "edata": "0000"})
     assert p == {"has_someone_duration": 0}
+
+
+def test_2691():
+    device = XDevice(2691)
+
+    p = device.decode({"eid": 4119, "edata": "3C000000"})
+    assert p == {"idle_time": 60}