Everything blinks when I apply the brake

[RVluvin]

2005 Fleetwood 36'. I added two additional tail light to the back of the trailer, mounted up high so my rig will be more visible, being the original tail lights are low and some what block by the wheels from the bicycles on the bike rack.
The 7 pin conector has turn signal and brake combined. At the rear of the trailer is a converter seperating the two with a built in blinker. (I can hear and feel in clicking. It also buzzez when the brake is applyed.)
I have tried tapping in front of this converter. I've tapped onto the back side of this converter with an addition converter returning back to the original turn signal/brake combined. I added a second pair of tail light just to seperate the turn signal and brake light, just like the manufacture tail lights are set up. No matter how I wire this, I keep getting the same result.
Running lights, turn signals, brake lights all work fine untill I apply the brake with a turn signal on, then every thing blinks.
2 additional bits of info: The 2 sets of lights I added are LED, with 3 wires and supposed to be set up for running lights and turn signal/brake combined.
Last year I experiance a blow out which tore up wires in the fender well, blowing fuses when all the wires got chewed. All that damage has since been repaired and fuses replaced.
Sorry this post is so long. So is the converter bad? Is the fact that I'm using LED lights the problem? Is it something else I'm missing? Should I eliminate that converter all together and use a heavy duty blinker in the truck? Please help.

[skipwil]

I think the first thing I'd do would do is to run a ground wire from the truck chassis to the frame of the trailer. Jumper cables work fine for this = make sure they are into the metal. Test everything again. If there's still the same problem = run a long wire from the jumper cable to the rear lights & connect into the ground system. A bad or frayed ground wire on a trailer will drive you batty or to drink or smack the pup. Your're depending on maybe one small sheet metal screw to ground the whole system & that many lights will feed back into the other lights.
safe travels...

[RVluvin]

Thank you Skip Wil for your sugestion. Problem solved, the converter was bad. Who ever checks their blinkers with someone applying the brake. Well I do now. I was able to just bypass the converter, and all the lights function as they should.

[JohnRR]

Thank you for the update, they can be as important as the original question at times.