2005 peterbilt 379 slow blinking directionals

Whats up guys .I need a little advice about a situation im having. My turn signals are blinking slow.I changed the directional switch on the column and they worked fine for a day then went back to going slow. They blink slow for about 5-6 blinks then pick up speed. When it rains they seem to work fine !? Ive seen a few posts here n there about a resistor for LED's ? I have LED lights all around. If this is a common problem where would a resistor be installed ? If not could it be the flasher going bad or Ive also seen a few people mention a flasher specific for LED M262?

Any input would be greatly appreciated .

All lights do work and flash accordingly....but slow.