This device is more than advertised, it's really a fully functional stereo pre-amp. I was able to remove my pre-amp from my system and use this to feed directly to my amp. It has everything you need for a high quality stereo setup. Easy to use volume and input controls, quick access to bass and treble controls, and the build quality is top notch. Since I use IOS (Airplay) for streaming over WiFi, I'm "limited" to 44.1 kHz, 16 bit, but it sounds incredible. Seriously, if you need a small unit to act as a Jack of All Trades to feed an amplifier, this unit is the way to go. There are a couple of little things that need to be improved IMO, so I gave it 4 stars for now. If I had to make some suggestions for improvements, here are a couple:

1) It has a Sub-Out which is GREAT, but there is no way to control it. You can't tell the unit what crossover point you want, nor can you tell it to use the main outs to act as a high pass filter. If you have a sub out, you should be able to use it as a sub-only out. Luckily my sub can do that, but I was hoping to be able to bypass that and just feed a sub signal to the sub and a high pass signal to the mains.
2) It has a couple of second delay when using AirPlay to play a song. Doesn't seem like a lot but it is a significant delay between every song when queuing up music. When I stream using Bluetooth there is no delay. When I streamed to my AirPort Express there was no delay. Not sure why there is one here.
3) The display is under-utilized. When using Bluetooth it just shows the Bluetooth symbol. When using AirPlay it just shows the song name. It would be nice to utilize the OLED a bit more. Maybe show the bitrate of the music being played?

I know those are nitpicks but for me it's what makes this item fall a little bit short of being PERFECT! It's an amazing unit just as it is, and I would highly recommend it to anyone. Hopefully these small issues can be addressed in the future with firmware upgrades.

The Audifi is a great looking unit, easy to set up and the sound is fantastic coming through my Rotel amp using the RCA outputs. I hope they update the app at some point so I can see lyrics and sample rate like I can with the native Amazon Music app, but so far very pleased with this purchase.

Seriously easy to set up, Audifi connected automatically to my Wifi network after opening the 4stream app. Using the supplied RCA cables, I connected Audifi to the available CD inputs of my amplifier - I haven't played a CD in many years. My usual source is Apple music on my iPhone with lossless enabled - the sound is terrific. Before Audifi I listened to music with Apple TV as the source. With Audifi the sound is clearer and richer. The downside is the front display text size - other than the volume numbers - the display cannot be seen from a distance. In fact, I need reading glasses to read the text. So that is where the 4stream app comes in. You can access most music sources (not Apple music) from the app and this will be your primary interaction with Audifi with the exception cannot power on/off the device. To turn on the device, you need to use the supplied remote control, and you can control many other functions with the remote control, but because I can't read the display, I find myself standing next to the Audifi while using the remote control.

Sound is great. Instructions would be improved by saying you should use the remote control to turn it on.

Hooked my audifi up to my NAD 725BEE and let her rip. This is why I bought this reciever in the first place. What a sound stage! Every song at the tip of my fingers. No more aux cords or cast. The quality is amazing.