USA Withholdings on Foreign Partner's Share of Partnership Pass-Through Income

[annabuzh]

I have a foreign-Owned LLC client. Per my understanding there supposed to be a withholding on the pass-thorough share of income to foreign partners at the highest rate. The foreign partners then file non-resident tax returns and claim refund on over withheld taxes. But it seems to be overly burdensome to do it this way. During one of the seminars the speaker said there might be no requirement to withhold when no distributions were made. However, I cannot find a confirmation of that statement anywhere. Am I missing anything? Or the speaker is deeply mistaken?