In this work we present a detailed discussion of the various sources of errors in commercial off the shelf (COTS) wireless sensor node (WSN) platforms through a series of experiments. These COTS WSNs are programmed using the TinyOS 2.x standard components and interfaces. The experimental setup is used to record an impulsive acoustic signal from several sensor nodes' microphones and send to the base-station for processing. The Flooding Time Synchronization Protocol (FTSP) was used, and a special MATLAB interfacing code was written to analyze and present the errors within this acquisition setup. It was found that there are at least 4 error sources that can dramatically degrade the signal acquisition due to the fact that standard TinyOS components are not suitable for medium/high sampling frequency applications.