\documentclass[a4paper]{book}
\usepackage{blindtext}

\usepackage[acronym]{glossaries}
	\newacronym{RS}{RS}{Reed--Solomon}

\title{Problem with glossaries and running headings}
\author{Joschi Brauchle}

\begin{document}
\maketitle

\frontmatter
	\tableofcontents 
\mainmatter

\chapter{Introduction}
	\blindtext[1]

\section{Get started with {\acrshort{RS}} codes}
	\blindtext[20]

\end{document}
