CGM features and fixes · SIBIONICS GS1

SIBIONICS GS1 alarms not sounding

Alarms need the app running in the background, alarms on, enough volume, and the phone within 6 meters (20 feet) of the sensor. There are no alarms during the 1-hour warm-up. (SIBIONICS user guide, p. 33; SIBIONICS user guide, p. 38)

What the maker says to do

1. Do not force-close the app.
2. Keep the alarm function on in the app.
3. Keep the volume loud enough to hear the alarms.
4. Turn on Override Do Not Disturb and allow Critical Alerts on iPhone.
5. Keep the phone within 6 meters (20 feet) of the sensor.
6. Keep the phone charged.

The GS1 is not FDA-cleared and is not sold in the US; these answers come from SIBIONICS's EU/UK English user guide, its sibionicscgm.com pages and the UK App Store.

More on the SIBIONICS GS1

• Signal loss
• Sensor error
• Warm-up
• Sensor failed early
• Compatible phones

Alarms not sounding on other CGMs

• Dexcom G6
• Dexcom G7
• Dexcom ONE+
• Dexcom Stelo
• FreeStyle Libre 2 and 2 Plus
• FreeStyle Libre 3 and 3 Plus
• Medtrum TouchCare Nano CGM
• Eversense 365
• Medtronic Simplera

Sources, quoted

• SIBIONICS user guide, p. 33: “Avoid forcing the App to close. To receive alarms, the App needs to be operating in the background.”
• SIBIONICS user guide, p. 38: “Alarms turned off: Keep the alarm function in the smartphone app and/or the smartwatch app turned on to get alarms.”
• SIBIONICS user guide, p. 38: “Volume not working: Keep the volume loud enough to hear the alarms.”
• SIBIONICS user guide, p. 33: “For iOS: You must accept the App's permission request for Critical Alerts to use this feature.”
• SIBIONICS user guide, p. 33: “Turn the Override Do Not Disturb setting in the App ON for Urgent Low Glucose, Low Glucose, High Glucose, and Signal Loss Alarms”
• SIBIONICS user guide, p. 38: “Out of range: Keep your display device no more than 6 meters (20 feet) from the sensor, with no obstacles between them, to ensure proper communication.”
• SIBIONICS user guide, p. 38: “Battery charge too low: If the display device battery is depleted, no GS1 readings or alarms will be obtained.”
• SIBIONICS user guide, p. 38: “No alarms or GS1 readings will be obtained during the 1-hour warmup or after a sensor session ends.”

Every quote is checked against its source page before each update of this site; last checked 2026-10-06. Makers change their apps; the source page is the authority when it differs.