I adjusted all of the settings in various ways, and am currently at:
Options > Audio > Device Settings > Buffering > Software: 1000 milliseconds
Options > Audio > Device Settings > Buffering > Hardware: Maximum
Options > Audio > Settings > Prebuffering: 20 seconds
From what I see, these are the maximums for each respective setting. I'm unfortunately still experiencing stuttering / dropouts, again with no correlating items in the log.
On the log, I have a question. I have seen a lot of messages like the following:
414299874: 16916480: General: CFileSystemManager::AnalyzeDrive: Drive does not exist (drive: D:, filename: D:\Music\...)
The D: drive exists only on the remote server, as my client is on OS X. I thought this might be related to the following setting:
Options > Media Network > Client Options (when connected to a Library Server) > Play local file if one that matches Library Server file is found
However, this option has been unchecked from the outset. I'm unsure if the above log message example is of any import to my audio issue, but am nonetheless curious about it.