Nexus 5X internal speaker is worse than Nexus5!

I hear distortion sound from default ringtone since I received N5X. Its totally different sound from listening by Headphone. I remember that N5 was not like this. even N5 has terrible speaker.
do I need to contact google and exchange to new one??

Trouble detecting Nexus5 on Windows

I am trying to install Marshmellow on my Nexus5, which currently has developer preview 3 on it.
I am following the process mentioned here: https://www.androidpit.com/how-to-get-android-m-preview
I have installed SDK tools but when I connect my Nexus5 to the computer then it is not showing up in the device manager.
USB debugging has been enabled as well. Can anyone please help me out here?

Thank you in advance