SmartSVN (OS X 10.7.5) Show Changes Error (Broken pipe PROPFIND request failed)

I can browse the repository, update and commit OK. I can show the log history for a file OK and show changes opens properly. However, from the Transactions pane, when I try to show changes on a single file, I get: Broken pipe PROPFIND request failed on '/repo/path/!svn/bc/12945/branches/mybranch/src/MyFile.mm'. It takes 20-30 seconds for the error message to report the failure.

Any help is much appreciated, thanks!

SmartSVN 7.5.2 (Mac OS X 10.7.5)
Subversion 1.7.7
Apache 2.2.22 (SSL)