Ipod 5 video rockbox slow track skipping?

[BenzilLobo]

I have rockbox installed on an Ipod 5th Gen Video. It is not in the best of condition and I have had it for years!!
I have installed a 'tarkan' iflash adaptor that allows an SD card to be in the place of the Hard drive. I have put a 'Qumox' 128GB card in and it all seems to work fine.... apart from a slight issue when skipping songs.

When I skip forward a track, on some albums, or even some sections of an album, the ipod seems to take upto 10 seconds to actually change the song. The screen will show the name of the next track almost immediately when pressing the 'forward' button, and the song time counter (bottom left) will change to 0:00....but the actual track wont play for upto ten seconds. when this happens, the song I was listening to will keep playing.

I have experimented with removing the artwork from the MP3s and this seems to have helped a lot but it still not as fast as i remember the original ipod OS being. Also, If I load a 'temperamental' album (an album where this issue really is occurring consistently) into a playlist into VLC player on my laptop the tracks skip fine on there so surely you would expect the same on my Ipod?

Although now I am using a 'qumox' card beforehand I was using a Phillips 128GB card and still the same issue happened.

Has anyone else had this issue.... can anyone help as Im running out of hair to pull out!!!???
Is there a way of checking the MP3s (and FLACS as I have a few of those) file integrity? is there a way to check for any artwork issues or a way of disabling it full stop??

Any help is most appreciated.