Quality of TuneIn via Alexa poor vs Sonos App

The app and Alexa are just different ways of ordering up the same thing. The app is just a controller and does no audio processing at all. Maybe you hit a low quality stream by chance when you used Alexa. I don't actually use voice control, though, so let's see if anyone has an alternative explanation.

I just set up my Sonos system, the Alexa integration was what made it accessible enough for my family. I noticed today while testing on my in-wall speakers that the radio station we usually listen to via FM sounded pretty bad. Asked Alexa to play the station, started playing via TuneIn on Alexa, but it was missing depth. I tweaked the EQ and loudness, which didn't help much. Then I tried listening to the same radio station via TuneIn in the Sonos app and it sounds great. My guess is that the playback via Alexa is highly compressed or a low bit rate, but frankly I'm not sure.

Is there any way to get TuneIn via Alexa to sound as good as TuneIn via Sonos?

I have the exact same issue and it is consistent. It appears to be an Alexa problem as it happens no matter if I play to my Alexa-enabled Sonos, via a Dot to Sonos or even directly on an Echo 😞 We probably need to complain to Amazon

I've done significant troubleshooting with Sonos and TuneIn, here's the latest:
- When you request a station via Alexa, it does not send the request to Sonos to stream TuneIn directly. Instead it is playing TuneIn on the Alexa side and playing it on the Sonos speaker.
- Not all stations exhibit this behaviour. Some sound terrible, some sound fine via Alexa.
- You can recreate the issue with the TuneIn iOS app as well. The stations I'm having troubles with via Alexa are also sounding bad via the TuneIn iOS app. In the iOS app, you can select an alternate stream. In all of my cases, the 48kbps MP3 stream is bad but a 40kbps AAC stream sounds great.
- Alexa is choosing the MP3 stream which sounds terrible. Sonos is choosing the AAC stream.
- There is no way via the Alexa app to choose a better stream

I recommend you open a support ticket with TuneIn. They've escalated my issue to development and another report will help with the priority I'm sure. I can see a few fixes - tag the better AAC stream as the default stream on the offending stations, determine if there is a common link with all of the 48kbps streams (common service provider maybe) and work with them to fix the stream, or other options. Manual stream selection via Alexa won't help, nobody in my family would ever do that.

-Pete

It's entirely possible that for whatever reason, streams through Alexa could be using a different bitrate or a different audio format than those requested through the Sonos app. Alexa serves a variety of devices, including Sonos, so they may be using a lower common denominator than Sonos uses when you request a station with the Sonos app. It also likely depends on the audio formats and bitrates available... some stations have many options, some might only have one or two.

I can't speak with certainty, but I would imagine that Sonos would favor AAC streams over MP3... AAC tends to have slightly better audio quality at lower bit rates, especially the AAC-HE (high efficiency) variant. Amazon may be using MP3 streams for wider compatibility, when the option is available, since they support a range of devices from many manufacturers.

So if a station has both formats available, that might explain the difference in audio quality between using the Sonos app and Alexa.