I have had similar issues with my '20 Optima which I've had since around Oct/Nov. All of my music is digital (USB or MP3) and the story goes when I try a new source for the 1st time whether it is CarPlay using iPhone (I was desperate), Bluetooth with my new player, Aux with my old, USB with flash drive; they all come on sounding like you'd expect a unit of this caliber to sound. Then once you start driving and using it-- the sound levels off, everything becomes flat, bass fades out like the sunset, etc etc. Clarity and separation are great, particularly with the Surround setting on, but it is as if these head units either have a piss poor quality DAC (or a non-existent one) or everything is wired to cut off at a certain level leaving you with a base line the manufacturer deemed fit for us to live with. Even on the highway I can only have the volume in the 7-10 range because even at that level my ears crack since the sonics are so out of whack. It is very hard to explain but it is depressing and I am at a loss as to where to go next in an attempt to rectify this. Any late-model Kia owners that have thoughts or ideas based on their own experiences would be highly appreciated.
You need to disable SDVC, and use the AUX input. Set EQ to flat, and use the source's own EQ and Preamp.
I have done this and much like everything else, it will sound fine at 1st but eventually "blends into the car" if that makes any sense. Initially I thought this would be my best option because at baseline with everything both in the MP3 Player (Sony NW-A45) and the car, I would then engage the Equalizer setting on the player I use for headphones and then use the Bass increase in the car to fill that out a bit for a balanced sound. Initially it will sound fine, even with Surround feature on. But after a few drives or stops he sonics flucuate. The best way I can explain it is in my 2012 Sonata in which I actually kept all factory audio installed, I knew exactly what my Volume settings were for Driveway, In Town, or Highway; and it was like 2 point spread between each (8, 10, 12) for example. Yes I am aware digital files have their own sound field and fluctuations depending on age, production, etc so that isn't what I am up against. This car I cannot even land on a comfortable Volume environment because it goes up and down from drive to drive. The car has some sort of "intuitive" feature that modifies the sound field based on preset conditions and it doesn't matter what audio source you are using. Hard to explain but true.
Hmm, yeah, best thing to do is delve into the audio settings, and see if you can disable whatever feature is causing this... and swap out your speakers.
My 18 LX is similar, I have an iPhone and I get better volume via Bluetooth than I do using CarPlay, but still mainly use CarPlay for the features. I did some searching around when I first got mine about the horrible bass response and all around craziness of the speakers. What I found out is that Kia’s firmware in their source units limits the frequency at higher volumes in order to protect the speakers from distorting especially when it come to the low end. All I did was buy an Audiocontrol LC2i and and added a 10” sub to round out the low end and it’s actually pretty decent. I would’ve gone all out and put my high end system in it, but I bought the bumper to bumper warranty and I didn’t want to run the risk of voiding anything as the stealerships kinda like to screw you on that kind of stuff whenever they can, like when they didn’t want to replace my dome light when the button wouldn’t spring back because I put in a blue led bulb in it, long story short it was replaced.
Thank you for this actually. My audio team thought this would be the best option as well given that the Treble & Mid have pretty decent range but the bass has none (not to mention what little there is has very off-putting quality). The only 2 things I was still researching was whether to stick with the LC2i w/the new sub or consider going with a multi-channel model instead. There seem to be conflicting trains of thought on the subject of whether to do so. The other was looking into potentially adding a DSP, especially since I'm probably stuck with the head unit. I really don't like the output of my digital files on this receiver but I notice the poor bass distorts a lot so am praying by taking the factory bass out of play, the rest will balance out and not sound as painful to the ears as it currently does.
Let us know how it turns out. My '13 LX is probably one of the last "dumb" generations of head unit that only had SDVC.
Gee · updated 
Munky · updated 
Patmasse · updated 
