ETSI TR 126 978 provides background information on the performance of the six candidates which were proposed as solutions for publication of an example noise suppression solution for application to the GSM Adaptive Multi-Rate (AMR) speech codec. Experimental test results from the speech quality related testing are reported to illustrate the behaviour of the candidate algorithms in multiple operational conditions. Additional information is also provided covering data not necessarily directly associated with speech quality (such as complexity, delay, effect on voice activity factor).