This paper presents the speaker verification systems developed in the LIA lab at the University of Avignon for the SITW (Speakers In The Wild) challenge. We present the algorithms used to deal with additive noise, short utterances and propose an improved scoring scheme using a discriminative classifier and integrating the homogeneity of the two compared recordings. Due to the heterogeneity of this database (presence of background noise, reverberation, Lombard effect, etc.), it is hard to analyze the contribution of individual techniques used to deal with each problem. For this reason, a subset of the trials will be studied for each algorithm in order to emphasize its contribution.