Can a brake controller get weaker over time?

I have a Tekonsha Primus brake controller which was installed in my truck when it was new in 2005. Lately it seems like it's not stopping my trailer like it should, even with the gain turned all the way up. I adjusted the brakes themselves and it helped a little, but still not grabbing like it seems like it should. I'm thinking about going to a Prodigy to see if that helps...