Reproducibility of replicate reactions can be optimised by considering the following: For low copy numbers of template, variable amplification could be because the limit of detection for an assay is being reached or because of differential agitation of reactions (with poorly agitated reactions not amplifying as well). Alternatively, the recombinase and ancillary protein in the 20x Core Reaction Mix are known to co-precipitate in 50% glycerol when stored at low temperatures. Warming the 20x Core Reaction Mix to room temperature and mixing will return them into solution, with no loss of function and could improve reproducibility. Variable amplification can also result from insufficiently mixed master mix. Users are advised to check post agitation that the 20x Core Reaction Mix is homogenous before adding it to reactions.