I bought some Pau D'arco bark, but it doesn't smell potent. It has only a slight smell. I've been making decoction tea out of it for about a week now, and I can't say I'm experiencing any of the die-off that many others are seeing. I purchased more Pau D'arco from mountainroseherbs, who always stocks fresh products.
Decoction is the way you should prepare D'arco. 1tbs per 1 cup of water. Heat to boil, add herb, lower to simmer. Simmer 10 to 20 minutes.