Blown speaker or defective amp?

Hi. Got a 2005 Prius with JBL Navigation.. Recently, my right speaker is no good as its making pfft pfft pfft bass-y sound. I had my local hybrid shop replaced the bad speaker with a excellent working one. It sound great now but sometimes I can hear soft pfft pfft deep bass sound..

Im hearing impaired and I have cochlear implant on my right ear and no hearing on left ear. I can tell that something is not sounding right yet..

Anyway, I played around with the MFD Sound setting and move the sound to the left side and right side. The left side sound fine but the right side sound like crap. Unless radio is playing in stereo which is suppose to be normal?


Also the speaker behind the MFD dont seem to work.. Is that speaker is for voice navigation only? I can upload the audio if you want to hear it? Hope you guys can help me out