Feedback when playing records

Hi guy/girls,

Looking for a little help/guidance please. I should point out that I'm a relative novice with limited technical understanding/knowledge so ask if you could please "dumb it down" for me 

I'm getting feedback through my speakers when playing records... mostly if the volume is cranked up and bass is high(ish). I turn the base down and the problem goes away... here's a pic of my (embarrassingly humble) setup - which I love by the way

I've had a read of the following topic but it doesn't really help...having said that I'm curious about the last comment and wonder if applies to me??