Upholstery and Fabrics - Hmmm...Cushion or spring problem?

I have a 7-year old couch (although admittedly not the highest of quality, but I was just starting out) that I actually absolutely loved...it WAS so comfortable for the first 5 years. In the past couple of years (and it's really gotten bad recently), the bottom of the backrest of the couch has a wooden beam that goes across the entire couch and it has become more and more prominent, to the point you can REALLY feel it digging into your back (near the bottom) when you sit down.

Blankets and pillows fall between the bar and the cushions very easily. I'm not a very crafty/handy person, so I'm looking for an easy fix. I've seen the ads for the 'sofa savers' and I've seen DIY suggestions to replace the cushions (they are foam with a zippered covers)...and I'm wondering if someone can tell me if my problem sounds like one that would be remedied by one of these solutions...is the problem the springs or the cushions? Thanks in advance for any suggestions...