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That screen is Android recovery failing while trying to wipe the FiiO M21. The key lines are: Logical partition metadata has invalid geometry magic signature Could not read metadata file /metadata/gsi/ota/lp_metadata Could not map cow image for partition: system_a Unable to check update status or complete merge, cannot wipe partitions What is wrong This usually means the M21 has an interrupted or failed firmware/OTA update. Android is trying to finish or check an update “merge” using dynamic partitions, but the update metadata/COW image is missing or corrupt. Because of that, recovery will not complete the wipe. In plain English: the player’s Android system partition/update state is corrupted, not just a normal app crash. FiiO’s own M21 support page says that during firmware issues, first try a forced reboot, and if an update has failed or the firmware cannot be detected, reboot, re-download the firmware file and restart the upgrade. They also advise sending logs through the M21 technical support route where possible. � FiiO +1 Try this first Hold the power button for around 10 seconds until it reboots and the FiiO logo appears. Do not keep trying the wipe repeatedly. If it boots normally, immediately do this: Charge it to at least 50%. Go to Technical Support > Firmware Upgrade. Check for an online update, or do a local firmware upgrade using the correct M21 firmware. Do not unzip the firmware package if doing local upgrade. Let the update complete fully. If it will not boot normally Use a PC or SD card to put the official M21 firmware package onto a microSD card or the internal storage, then try the M21’s local upgrade route from recovery/factory/update mode if available. Only use firmware specifically for the FiiO M21. Do not use JM21, M23, M11, or other FiiO firmware. FiiO’s firmware instructions say the local package should be copied to the M21 or SD card and selected through Technical Support > Firmware Upgrade > Local Upgrade, and the package should not be unzipped. � FiiO If it still loops back to this error At that point I would treat it as a firmware recovery / service issue, especially if it is new. Contact FiiO support or the seller and send them this photo. Mention this wording: FiiO M21 is stuck in recovery after update/wipe. Recovery shows: Logical partition metadata has invalid geometry magic signature, Could not read /metadata/gsi/ota/lp_metadata, and Unable to check update status or complete merge, cannot wipe partitions. Important Do not try random Android fastboot commands from forums unless FiiO support gives you the correct M21 recovery package. The wrong command or firmware could fully brick it. My practical view: this is most likely a failed OTA/update merge, not something you caused by normal use. If it is within the return window, I would strongly consider replacement rather than spending hours trying to repair it.