WhatsApp for LG Q8

Open Settings > Battery to see the per-app usage breakdown and force-stop anything draining power in the background. Turn on Battery saver, then lower brightness and screen timeout under Settings > Display, and disable Always-on display if it's enabled. Also revoke background location for apps that don't need it under Settings > Apps > [app] > Permissions > Location, since constant GPS polling is a common hidden drain. See how others solved this on Reddit

Wipe the proximity sensor area near the top of the screen first, because when it thinks the phone is at your ear it routes audio to the earpiece instead of the loudspeaker. Check Settings > Bluetooth for any paired device that's silently grabbing the audio, and toggle Bluetooth off to confirm. If it persists, go to Settings > Apps > WhatsApp > Storage and clear the cache, then reopen and play a message with the phone flat on a table. See how others solved this on Reddit

A bad or non-data USB cable is the usual culprit, so swap to a short, high-quality cable and plug directly into the car's main USB port rather than a hub. In Settings > Apps > Android Auto > Storage, clear the cache, and confirm Android Auto is updated from the Play Store. Then turn off battery optimization for it under Settings > Apps > Android Auto > Battery so the system stops killing it, and disable any aggressive battery saver mode while driving. See how others solved this on Reddit

Re-pair the phone fresh via Settings > Connected devices > Bluetooth, removing the old car profile first so a stale pairing isn't holding the audio channel. Make sure Media audio is enabled for the car under that paired device's settings, and that WhatsApp has microphone permission under Settings > Apps > WhatsApp > Permissions. If voice notes still route to the phone speaker instead of the car, restart both the phone and the head unit to reset the audio routing. See how others solved this on Reddit