I was reading Brown's Cohomology Theory of Finite groups and  was wondering whether there's an example of the following. 

Let $n\in \mathbb{N}$ does there exist a $\mathbb{Z}_n$ module $M$ which is cohomologically trivial (i.e. $\hat{H}^i(\mathbb{Z}_n,M)$ is trivial for each $i$) but such that there exists some $p,i\in \mathbb{N}$ such that $\hat{H}^i(\mathbb{Z}_n,M/pM)$ is non-trivial? 

In the case that $M$ has no $n$ torsion this is not possible by Lemma 8.6 of Brown's Cohomology of groups, I was wondering what goes wrong in the sense of a counterexample when $M$ has $n$ torsion.