Iphone 11 Pro bottom speaker distortion

Okay, so when i got my 11 pro i remember the speakers sounding great. I didnt use the phone much due to having airpods, However i noticed recently it wasnt the same, cleaned the grills earlier with a soft brush and the bottom speaker is now louder again, but sounds very distorted and low quality especially compared to the top speaker/earpiece when playing music etc. Anyone else had this issue and is it likely to be hardware? Cant really be bothered with the whole going in store thing to change/repair it but i guess i may have too. Anyone had similar and any advice?