Your Echo Show 21 screen lights up, the clock displays, but "Alexa" gets nothing back. No blue ring. No voice response. The microphone has stopped listening. This is a common issue with the 21-inch display, and it usually comes down to a handful of things you can check in a minute or two.
First, look at the top edge of the display. There's a physical button with a microphone icon (and sometimes a camera icon next to it). If the button has an orange indicator light or shows a red line through the mic, you've accidentally muted it. Press the button once. The light turns off, and Alexa starts listening again immediately.
Check the Mute Button and Camera Privacy Shutter
The Echo Show 21 has a dedicated mute button on the top bezel. Press it. If the mic was muted, you'll see a brief animation on screen confirming unmute. The camera also has a privacy shutter you can slide closed. If the shutter is closed, the mic might still work, but the camera won't. That's separate from the mic issue, but worth a quick glance.
If the mute button doesn't respond, try pressing it multiple times. Some units have a bit of travel that needs working in.
Power Cycle the Display
Unplug the AC adapter from the back of the Echo Show 21. Wait 30 seconds, then plug it back in. The display takes about 60 seconds to boot, and you'll hear the startup chime. This clears any stuck audio processing and is the single most common fix for unresponsive mics on Echo devices.
The Echo Show 21 uses a dedicated AC adapter, not USB-C, so make sure it's firmly seated in the port. A loose connection can cause intermittent power.
Make Sure the Wi-Fi Connection Is Solid
If the mic registers your voice but Alexa doesn't respond, the device may have lost its network connection. Swipe down from the top of the screen to open Quick Settings. Check that Wi-Fi is on and connected to your network. If it's showing a disconnected state, tap the Wi-Fi icon and reconnect to your home network.
The Echo Show 21 supports Wi-Fi 6E, which gives strong speeds but requires a compatible router. If you've recently changed your Wi-Fi password or router, the device won't reconnect automatically. You'll need to go into Settings > Network and re-enter the credentials.
Retrain Your Voice Profile
If the mic responds to other people in the house but not you, Alexa's voice profile has stopped recognizing you. Open the Alexa app, tap More > Settings > Your Voice. Select your profile and choose Re-train voice. Say a few phrases when prompted. This takes about 30 seconds and usually fixes recognition issues caused by a cold, allergies, or any voice change.
Voice profiles are stored per account. If you share the Echo Show 21, make sure each person has their own profile and that the device is set to recognize multiple voices.
Check for a Firmware Update
Amazon pushes updates automatically, but sometimes the device falls behind. Swipe down from the top, tap Settings > Device Options > Check for Software Updates. If an update is available, let it download and install. A reboot follows. Firmware updates can resolve microphone driver issues that Amazon may have patched.
Adjust Wake Word Sensitivity
Open the Alexa app, go to Devices, select your Echo Show 21, then tap Settings > Wake Word. You can choose from "Alexa," "Amazon," "Computer," or "Echo." If you've set a custom wake word, try switching back to "Alexa" temporarily to see if the issue is tied to a specific wake word. Also check Voice Responses to ensure the device isn't set to Quiet Mode or Do Not Disturb.
Known Issues That Can Affect the Mic
The Echo Show 21's 21.5-inch screen is huge, and some older Skills don't scale properly. If you notice microphone lag only when using a specific Skill, that Skill might be causing the issue. Uninstall the Skill through the Alexa app and see if the mic recovers.
Also, if you're using the built-in Fire TV interface, extended video streaming can sometimes cause the whole system to stutter, including mic input. A quick restart of Fire TV mode (go to Settings > Fire TV > Restart Fire TV) often clears it.
Picture frame mode can also interfere if it's actively cycling through photos. Swipe down on the screen and turn off Picture Frame mode for a moment to test the mic separately.
Test the Microphone Directly
Open the Alexa app on your phone. Tap the device tile for your Echo Show 21. Hold the mic icon and speak a command like "What's the weather?" If the Echo Show 21 responds normally, the mic hardware is working. If the app says the device is unreachable, the issue is network or account related.
You can also ask Alexa to "test the microphone", some firmware versions support this. If no response, move on to the next step.
Factory Reset the Echo Show 21
If nothing else works, a factory reset is your last step. Go to Settings > Device Options > Reset to Factory Defaults. Confirm the reset. The device wipes all personal settings, Wi-Fi credentials, and voice profiles. Set it up fresh via the Alexa app.
This resets everything, so only do it after you've tried the simpler fixes. It almost always brings the microphone back to life.
