96 sl shifting trouble.

I have a 96 sl that is difficult to shift into first at times. I have toyed with the cables and had them working good. Lately the problem is coming back. I was playing with the calbes again. Now, at times, I can not get it into 1st or 2nd unless I turn the engine off, or move the car somewhat. Also lately when at a stop light. In 1st gear, clutch in, I get a chugging action. So I pull it out of 1st into nuetral. Back into 1st then ok. Thinking Tranny problems. Any help is appreciated.