Modifications in the FASTPlaqueTB test protocol have resulted in an increase in the analytical limits of detection. This study investigated whether the performance of a modified prototype was able to increase the detection of smear-negative, culture-positive sputum samples as compared to the first generation FASTPlaqueTB test. Modifications to the FASTPlaqueTB did result in increased detection of smear-negative samples, but this was associated with a decrease in the specificity of the test. Before the FASTPlaqueTB can be considered as a viable replacement for smear microscopy and culture for the identification of tuberculosis, further work is required to resolve the performance issues identified in this study.