> I don't understand why this is the case. If usb out is digital out then why is there a change of sound?
There shouldn't be a change of sound if
a) your smartphones player is able to work bit perfect
b) if the music content is lossless
Please re-read Kai's post #5. You need to check, whether your player is able to play bit perfect. For that to work you need to deactivate everything what alters sound (Bass, Treble, Booster, EQ) and the volume level of the application needs to be at 100%.
You can also use the PC to pre-check an USB cable for the smartphone, if smartphone and PC have the same USB-C plug. if your PC doesn't have it, you can buy an additional expansion card. This would have the charm that you are then able to pretest the cable on the PC with the feature of the RME ASIO driver (in the settings dialog) that there are no errors during data transport (audio is also simply data).
If the bit perfect test succeeds and if quality is still not ok on smartphone, then its much likely that the music content is not in a lossless format or that you are comparing Smartphone vs PC with with different volume levels. Louder sounds always better to our ears.
Another possibility for perceiving differences between audio playback from smartphone
and from PC might be, that
a) your checks have a longer delay in between, our brain can only remember sound for short moments, why its necessary to make quick A/B tests
b) additionally personal expectation influences the perception.
c) you do not use the same volume level, louder sounds better to our ears (-> loudness war)
If you do not know all this, then its much likely that a combination of all this is what happens and makes you think, that something is different.
USB cable price is not relevant here, simply do not get the cheapest to get no issues with bad plugs.
I payed with €25 already a lot of money for such a cable because I needed a 5m USB3 cable and this is longer than the technical specs allow for USB3. So I invested into a 3x shielded Lindy premium cable for around €25 to be able to use a longer cable without issues.
On the PC you can install the RME ASIO driver and if you open the driver settings window and keep it open you can watch the CRC counter there, if they stay 0 then you have no USB transport issues.
Buying expensive USB cables is not required, its like buying a Rolls to drive to Mc Donalds. If you want to burn money, please do, but there is technically no requirement for this. It won't alter the sound in any way, its pure digital transmission.
RME Steadyclock eliminates any jitter and the fhe final D/A conversion is being performed on the ADI-2 Pro using its own internal Femto Second clock.
X10SRi-F, Win10 Pro 1909, Cubase, UFX+, Octamic XTC, ADI-2 Pro FS BE/R BE, RayDAT, ARC USB