Some examples relate to a system including a pulse modulation (PM) circuit having a PM input and a PM output. The system also includes a load circuit having a load circuit input, and an I/O pad coupling the PM output to the load circuit input. An asymmetry detection circuit has a first asymmetry detection (AD) input coupled to the PM output via a first feedback path, a second AD input coupled to an output node of the I/O pad via a second feedback path, and an AD output coupled to the PM input of the pulse modulation circuit via a control path.