CB 0.8.12 and cowboy error

[jim rosenblum]

I have a process which does a series of https posts, about 20 of them in a row, every 10 minutes.

About a third of the time, the following error appears on the CB 

[error] <0.238.0> Ranch listener boss_https_listener had connection process started with cowboy_protocol:start_link/4 at <0.502.0> exit with reason: {function_clause,[{cowboy_http,quoted_string,[<<"HqAlq8PjsqnzoxbCKKnG/h9C8Kg=">>,#Fun<cowboy_http.19.85016776>],[{file,"src/cowboy_http.erl"},{line,690}]},{cowboy_http,nonempty_list,2,[{file,"src/cowboy_http.erl"},{line,58}]},{cowboy_req,parse_header,4,[{file,"src/cowboy_req.erl"},{line,473}]},{cowboy_rest,if_none_match_exists,2,[{file,"src/cowboy_rest.erl"},{line,583}]},{cowboy_protocol,execute,4,[{file,"src/cowboy_protocol.erl"},{line,529}]}]}

on the client side, I get

[error] HTTP request failed socket_closed_remotely

Any help would be much appreciated.