Hello everyone! this is my first post after reading some reviews here and having bought the Fosi DS2 because of its technical achievements.
I can confirm
the annoying ramp up (or fade in) effect: this device is the nemesis of any system of notifications,
already based on this I wouldn't recommend it to anyone.
Based on my tests:
- On a Dell XPS 15 9500 with Windows 11 (the company laptop) I have experienced drop outs while listening to music.
- On my PC with Fedora 41 or a Samsung S23 (even this from my company) I haven't experienced drop outs while listening to music.
I would not recommend it at all for a Windows user, the driver from their site in my case causes even more frequent drop outs, buying this using Windows is a gamble.
On Linux you can remove the ramp up effect (hence it can work well for notifications) doing a loopback with no sound, something like this:
pactl load-module module-null-sink sink_name=keepalive
pactl load-module module-loopback source=keepalive.monitor
With the Samsung S23 I also heard some strange electrical noise (mainly while physically moving the DAC) but for now it doesn't seem serious.
My headphones are the Sennheiser HD 599 SE and before buying the Fosi I have bought a UGREEN USB-C to jack DAC.
I have bought the Fosi out of curiosity seeing this review and because I was thinking that the UGREEN was "too cheap to be good".
Between them the UGREEN is the clear winner
for my use case and setup:
- I don't ear the difference probably because the 599 SE are really easy to drive;
- It doesn't ramp up or drop out sounds on any of my devices;
- It is more portable (even if I don't care too much about this, the Fosi is already "enough portable" for me);
- It is cheaper, 10 euros vs 60 euros for the Fosi.
The only thing which is really important but I can't assess right now is the durability of both these DACs, time will tell.
The software and firmware issues with the Fosi in my opinion are a deal breaker, I will keep it but probably don't use it much.
In the end it was a waste of money for me but at least now I have some more experience about this stuff.
Thanks for reading, I hope that you find this useful!