Bolero Head unit MP3 problem

Hi I'm a newb to the site a big hello to all.

Crazy problem with my Bolero head unit, I am need of some advice. My car is a 2017 2.0 Yeti,  I have owned it for 10 months now. My head unit does not have the car play initialised. I like how quickly it connects my IPhone.

I listen to mainly MP3's, firstly it was off a USB stick and now an SD card. The problem I have is that the unit won't keep its memory for playback of the MP3's. At first, once or twice a week the unit used to reset to first folder on the USB. Most of my MP3's are audio lectures / podcasts and when it did this it was annoying finding the right folder and file again. Doesn't matter on the length, 5 mins or 40 mins.

Then I read somewhere that this maybe a USB related issue so I changed to an SD card, same problem. As time went on it has got worse, Now it either firstly and 99%  of time is constantly going to the beginning of the MP3 I am listening to, or going to first file on memory card. Seriously left me pulling out my hair, it's friggin annoying. I have reset it to factory settings and same issue, I am really stumped now. 

It has left me with two questions is there a SW update that can sort this issue out? or do I bite the bullet and buy an after market Head Unit Pioneer or Sony etc.? The only problem I'm assuming I'll Have with an after market Unit is that the on-screen parking aid image I get on the bolero Won't  work on after market unit? any help would be hugely appreciated.