Headphones? Speakers?
What solutions have you tried to date?
More information is needed about the problem.
Do you have the User Guide?
E.g.:
http://lgaristo.com/lg-aristo-user-owners-cellphone-manual-guide-pdf-download-metropcs-t-mobile/
If the preceding link does not provide the applicable manual, then google for the manual via the phone's model number.
Be sure that you have indeed configured the phone correctly.