Review on 🎧 High-Performance Bluetooth 5.0 USB DAC Headphone Amplifier: APTX HD/LDAC/APTX/APTX LL/DSD512 Supported, ES9038Q2M XMOS-XU208, PCM768kHz, HiFi Stereo Headphone Amp for 16Ω-300Ω Headphones - Desktop Powered/Home Audio by David Flores

This DAC works perfectly on Macbook Pro 2012 with Big Sur via USB, optical cable and iPhone 11 via Lightning to USB cable. It's a slight but noticeable improvement in sound quality, and the headphone amp easily handles the HD650. Used this to compare Bluetooth, USB at different bitrates, the DAC in my CD player and this ES9038Q2M, and several different headphone amps. The review claimed the build quality is questionable, but I disagree, it's solid enough for the price. Now I will use this DAC instead of the built-in DACs.