CSS clash with JW Player - when in html5 mode

Our website has JW Player, and functions well in a normal setting. However in Html5 mode, there is a CSS clash with the website and the Player causing distortions in initial appearance only - functioning of the Player is not a problem once play is pressed. We need someone who knows how to quickly identify which CSS is clashing in Html5 mode, and how to resolve that CSS clash. Distortion details: there is a grey bar cutting the Start-up image in half, and the background border of the Player which is website generated, is layered and not how it should look - see image attached. Preferably a person who has resolved CSS clash in Html5 mode before, or knows workarounds for CSS clash in Html5 mode. Simple job for a person who has done this before: offering $30 for immediate completion.