In my sun room I have 2 sets of 2 RGBs each with a controller, the controller sensors are right next to each other, like 1/4 inch apart, and it does not work for me, strips keeps getting out of sync. I am working on a fix to control both with 1 controller, with requires a 2 channel controller , which is another long story, ..... What you can do and it works is, if this fits your application, is connect 2 strips end to end, and insert a Hitlights LED Light strip amplifier booster , search on amazon,  between the 2 strips and power the first strip and the booster each with the standard little 2amp plug in power supply ( usually sold with the strips, but also sold separately ) More than 2 strips connected end to end exceeds the current limit for the first strip. I used the booster method to light up the wall on 32 feet of the layout in different colors, and it works fine.

Hope this helps ...Rick

Oh yea ... the booster is the one for $ 8.49