Audio system issues

[Jboff21]

Hey all 

just pursched an Audi a3 8p sline and absolutely love it. The issue I’m having is non of the front speakers are working very well including the tweaters. The car has a 10 inch Polaris headunit in it that was installed by the previous owner so not 100% sure if this is the reason. The balance settings on the headunit are set to all speakers but front ones are so so quiet. Has anyone else had this issue and can shed some light 

[Steve Q]

Was it bought privately or via a dealer?