I came across a bug in bxslider as when telling the slider to fade, it fades to the next slide but then fades out and flahes back in again.
I had the following set but no matter what i tweaked it still faded from one to another with an obvious flash effect.
mode: 'fade', slideSelector: '', infiniteLoop: true, hideControlOnEnd: false, speed: 500, easing: ', slideMargin: 0, startSlide: 0, randomStart: false, captions: false, ticker: false, tickerHover: false, adaptiveHeight: false, adaptiveHeightSpeed: 500, video: false, useCSS: false, preloadImages: 'visible', responsive: true, slideZIndex: 50, wrapperClass: 'bx-wrapper',
Apply the following direct to the page and it then fades from one banner to the other as expected. I found this fix on the internet so wanted to share.