AirPlay on Apple TV: Amazon states AirPlay is constrained to a 16-bit signal max, so you can forget about Ultra HD. Chromecast Audio: The CCA refuses to appear in the devices list hence casting from the Amazon app is not an option. All in the context of transferring a digital signal to a DAC. My quest has been mostly fruitless so far, even though my DAC accepts digital signals up to 24 bit and 96kHz (and will report the incoming sampling rate) preserving the original Amazon streamed bit depth and sampling rate. (Its icon looks like a piano.) Adjust the speaker or headphone Format setting to the highest sample rate for 24 bit (96 kHz or 192 kHz).Listen to Amazon Music HD and Ultra HD via a digital input (e.g.
Open Launchpad > Other > Audio MIDI Setup app. Any Mac from 2013 or later supports HD and Ultra HD, but you need to adjust the audio settings.(Alternatively, attempt to install the Amazon Music HD desktop app.) Check your computer’s specs or contact Amazon to determine if you’re compatible. PC support for HD and Ultra HD playback depends on the built-in audio player and DAC (digital-to-analog converter), which varies by device.Chromecast doesn't support Amazon Music HD. Please ensure that your device is running on Android Lollipop, or later. Most Android devices released since 2014 can support HD/Ultra HD playback (up to 48kHz).Apple AirPlay supports HD quality playback. To play songs at higher sample rates (96 or 192 kHz), iPhone customers can connect an external DAC capable of supporting those higher sample rates. Most iPhones and iPads released since 2014 (devices running on iOS 11, or later) can support HD/Ultra HD (up to 24-bit, 48kHz) without any additional equipment.The Echo Studio supports Ultra HD quality audio. Alexa-enabled Echo devices (2nd generation and later), Fire TVs, and Fire Tablets all support HD quality audio.