Those directives aren't enabled - but I don't see how they could be causing a content encoding error, as they're not dealing with content encoding, but rather compression (which anything gzip is passed as UTF-8)
I don't have a separate .htaccess file for that particular site, and the vhost entry for it is pretty vanilla. Simply some mod_rewrite to redirect people to the no-www version of the site, and the SSL cert info. I've tried to isolate the error in my logs (log level warn)
[Wed Nov 27 08:25:44 2013] [warn] [client 10.75.10.1] (104)Connection reset by peer: mod_fcgid: error reading data from FastCGI server, referer: http://vle.tiseagles.com/cache/admin.php
[Wed Nov 27 08:25:44 2013] [warn] [client 10.75.10.1] (104)Connection reset by peer: mod_fcgid: ap_pass_brigade failed in handle_request_ipc function, referer: http://vle.tiseagles.com/cache/admin.php
thanks for all your help with this, I really appreciate it! I hope I can get to the bottom of this soon.
Ah, able to find one more error that might be causing the above:
[Wed Nov 27 08:32:59 2013] [error] [client 10.75.10.1] Premature end of script headers: admin.php, referer: http://vle.tiseagles.com/cache/admin.php?action=editdefinitionmapping&sesskey=GGrAGr3jDg&definition=core%2Fstring
here's a full log dump, well partial but a larger capture, sorry there's other people on the server but you can tell anything I'm doing is using admin.php: