Errors with figure caption since using siunitx

Question

I am a bit of a newbie with LaTeX. Everything was working well (mostly) but I am running into all sorts of weird errors since I added the siunitx package. The error log first showed errors with tables, which I was able to fix (I think) using a quick tip on entry (thank you). Now the remaining errors originate from all my figure captions. It feels like siunitx is trying to parse my figure captions but is rejecting their content. I tried the same strategy as what fixed it for my tables (\sisetup{parse-numbers = false}), but it is still not working. Any ideas?

This is my simple code (works if siunitx is commented out):

\documentclass[12pt,letterpaper]{report}
%
% Review cuthesis.sty for more documentation on available options
% for this package.
%\usepackage[1committee,phd,nonsequential]{cuthesis}
\usepackage[3committee,masters,standard,nonsequential]{cuthesis} %Carleton University template
\usepackage{array}
\usepackage{graphicx}
\usepackage{color}
\usepackage{cite}
\usepackage{subfig}
\usepackage{amsmath}
\usepackage{rotating}
\usepackage{setspace}
\usepackage{longtable}
\usepackage[colorlinks=true,pdftex,bookmarks=true,bookmarksnumbered=true,breaklinks=true]{hyperref}
\usepackage{pdfsync}
%\usepackage{ucs}
\usepackage[utf8x]{inputenc}
%\usepackage[T1]{fontenc}
%\usepackage{siunitx} %used for the writing of SI units such as micro
\usepackage{hyperref} %used for pdf properties
%\usepackage[indent,bf]{caption}

\graphicspath{{figures/}}
\onehalfspacing

\title{Sandbox}

\begin{document}

% Define thesis title and author
\title{RD}
\author{FD}
\pastdegrees{B.Eng.}
\dept{Systems and Computer Engineering}
\degreename{Master of Applied Science in Electrical Engineering}


% Specify your Thesis Submission Date
\submitdate{May, 2012} \copyrightyear{2012} \copyrightmonth{May}

% Thesis committee information for the signature page
% Be sure to specify size of committee in cuthesis options.
% Department Chair does not count as a committee member.
% ie: 1committee = department chair  (doesn't make sense)
%     2committee = firstcommittee + department chair
%     3committee = firstcommittee + secondcommittee + department chair
%     4committee = firstcommittee + secondcommittee + thirdcommittee + department chair
% Default setting is 1committee
\firstcommittee{Professor MS, Thesis Supervisor}
\secondcommittee{Professor MB, Examiner}
\thirdcommittee{Professor "Name", Thesis Co-supervisor}

% Specify department chair
\departmentchair{Professor HS, Chair,\\Department of Systems and Computer Engineering}


\section{whatever}
la la

\begin{figure}
  % Requires \usepackage{graphicx} 
  %TODO regenerate this graph with matlab
  \centering
  \includegraphics[width=4in]{OFDMspectrum-single.png}
  \caption{Spectrum of a single modulated OFDM subcarrier (truncated).}  \label{fig:single}
\end{figure}

\end{document}

Answer 1

(This is a bit too long for a comment.)

If you work through to create a MWE, the problem can be isolated to a document consisting of

\documentclass{article}

\usepackage{cuthesis}
\usepackage{calc}

\begin{document}
\begin{figure}
  \caption{Demo}
\end{figure}

\end{document}

The calc package is entirely standard, so this is a bug in cuthesis.

(The problem shows up with siunitx as it loads calc.)