WhatsApp for Xperia 1 VI

This is usually a permissions or audio-routing issue rather than a hardware fault. Go to Settings > Apps > WhatsApp > Permissions and make sure Microphone is set to Allow, then place a normal phone call to confirm the mic works system-wide. If it still fails, clear WhatsApp's cache under Settings > Apps > WhatsApp > Storage > Clear cache and reboot. If the mic works in regular calls but not in third-party apps, make sure both Android and WhatsApp are fully updated, since the fix usually arrives in an app or system update. See how others solved this on Reddit

Android's call handling and battery optimization can stop WhatsApp from grabbing the Bluetooth audio channel, especially when the screen is off. Go to Settings > Apps > WhatsApp > App battery usage and set it to Unrestricted, and confirm the Nearby devices and Phone permissions are granted under Settings > Apps > WhatsApp > Permissions. Then re-pair the headset under Settings > Device connection > Bluetooth and make sure both Call audio and Media audio are enabled for that device, since a half-connected profile is a common cause of calls you can't answer. See how others solved this on Reddit

WhatsApp uses its own built-in camera for in-chat photos and does not call the dedicated Sony Camera or Photography Pro app, so shots taken inside a chat look softer than native ones. To get full Xperia camera quality, take the photo first with the Sony camera app, then share it into WhatsApp via the attachment (paperclip) > Gallery picker. There is no setting to make WhatsApp's shutter use the system camera. See how others solved this on Reddit

Heavy drain usually comes from WhatsApp staying active in the background plus frequent media auto-download. First confirm the culprit under Settings > Battery > Battery usage. Then turn off auto-download in WhatsApp > Settings > Storage and data, and update WhatsApp from the Play Store in case a buggy version is to blame. Avoid setting WhatsApp to Restricted under Settings > Apps > WhatsApp > App battery usage if you rely on timely message and call notifications, as Restricted can delay them; use Optimized instead. See how others solved this on Reddit

The Xperia 1 VI's dual front speakers plus its audio enhancements can affect how WhatsApp voice notes and call audio sound. Try turning off Dolby Atmos under Settings > Sound & vibration > Audio settings and test again, then clear WhatsApp's cache via Settings > Apps > WhatsApp > Storage. For voice notes, remember WhatsApp plays them through the earpiece when the phone is near your face and switches to the loudspeaker when you hold it away, which the proximity sensor controls, so a dirty or covered sensor can make playback seem to come from the wrong speaker. See how others solved this on Reddit

Sony's battery management can delay WhatsApp notifications and freeze background activity for social apps. For each app, go to Settings > Apps > [app] > App battery usage and set it to Unrestricted, and turn off STAMINA mode under Settings > Battery if you need instant message delivery. If notifications still arrive late, the app may be getting limited by Adaptive Battery, which you can disable under Settings > Battery > Adaptive Battery. See how others solved this on Reddit