🎧 Sound & Bluetooth: The RUIZU delivers crisp, balanced audio that rivals the legendary Sansa Clip. Bluetooth 5.3 connects instantly to my earbuds during gym sessions, though wired headphones (like my trusty KZ ZSN Pros) reveal slightly richer bass. A minor quirk: holding the 'up' button locks the screen mid-scroll – annoying when speed-navigating my 80GB punk rock collection.

📁 Storage & Transfer: The 64GB internal + 128GB expandable storage is a dream! I loaded 12,000 songs via microSD (way faster than USB-C transfers). Pro tip: Use the OEM cable for file transfers – generic USB-C cables only charge. Folder view keeps my audiobooks/music neatly separated, though long filenames get truncated.

🏃 Workout Companion: At just 25g, this clips securely to running shorts. The pedometer tracked my 5K route within 5% accuracy vs my Garmin. Battery lasts through marathon training weeks (18-20hrs), and the matte red finish survived sweaty HIIT sessions without slipping.

🔋 Charging Quirks: While 1.5hr fast charging works as advertised, I wish it supported wireless charging. The non-standard USB-C port means losing the included cable could be problematic – I’ve already ordered a spare after mine nearly got lost in gym bag chaos.

🎛️ Button Layout: There’s a learning curve – ‘left’ and ‘down’ both function as ‘back’ in different menus. After two weeks, muscle memory kicked in, but my tech-challenged dad still struggles. The clip feels sturdy but I baby it after one reviewer mentioned fragility.

The RUIZU isn’t perfect, but at this price? It’s resurrected my love for dedicated MP3 players – no phone distractions, just pure music nostalgia with modern Bluetooth convenience.