Recently a new attempt to go beyond quantum mechanics (QM) was presented in the form of so called prequantum classical statistical field theory (PCSFT). Its main experimental prediction is violation of Borns rule which provides only an approximative description of real probabilities. We expect that it will be possible to design numerous experiments demonstrating violation of Borns rule. Moreover, recently the first experimental evidence of violation was found in the triple slits interference experiment, see cite{WWW}. Although this experimental test was motivated by another prequantum model, it can be definitely considered as at least preliminary confirmation of the main prediction of PCSFT. In our approach quantum particles are just symbolic representations of prequantum random fields, e.g., electron-field or neutron-field; photon is associated with classical random electromagnetic field. Such prequantum fields fluctuate on time and space scales which are essentially finer than scales of QM, cf. `t Hoofts attempt to go beyond QM cite{H1}--cite{TH2}. In this paper we elaborate a detection model in the PCSFT-framework. In this model classical random fields (corresponding to quantum particles) interact with detectors inducing probabilities which match with Borns rule only approximately. Thus QM arises from PCSFT as an approximative theory. New tests of violation of Borns rule are proposed.