Channel hopping is a well-known methodology to dynamically allocate frequency resources to nodes in wireless communication systems. The aim of channel hopping is to mitigate possible interference issues caused by both legitimate and malicious users. The stateof-the-art channel hopping-based jamming mitigation techniques are becoming increasingly smart by using game theory or machine learning. However, we show in this paper that, although the victim may employ smart channel hopping strategies, these are not always effective in mitigating attacks. In this paper, we implement an effective jamming attack strategy to impair the effectiveness of channel hopping mitigation strategies. We test our attack on a testbed network composed by real devices, and test its effectiveness against three mitigation strategies: i) incremental channel hopping, ii) random channel hopping, and iii) smart channel hopping. We show that, by implementing our attack, an attacker can reduce the number of successfully transmitted packets by at least 28.5%, even against the smart channel hopping strategy.