Poor bluetooth headphone reception from i Mac

I have purchased photive PH-BTE50 bluetooth earbuds which I have paired with my iPhone 5 and my iPad air without problem,however they do not pair with my iTV2[TV not finding the earbuds] and though paired with my iMac [2.7 i5 mid 2011] the sound quality is poor with drop outs continually.I have other wi-fi headphones that work well but not the new Photive bluetooth buds