diff --git a/eoptasks/eoptasks.py b/eoptasks/eoptasks.py
index 492f8d0..bb00161 100755
--- a/eoptasks/eoptasks.py
+++ b/eoptasks/eoptasks.py
@@ -218,7 +218,9 @@ def command_window(args):
         cmd += ' ' + ' '.join(['"%s"' % x for x in args.args])
     orig_cmd = cmd
     while True:
-        rc = subprocess.call(['ssh', '-t', args.command_server_name] + [cmd])
+        # -t: force a tty for interactive commands.
+        # -S none: disable connection sharing as it proved unreliable.
+        rc = subprocess.call(['ssh', '-t', '-o', 'ControlMaster=no', '-S', 'none', args.command_server_name] + [cmd])
         if rc == 0:
             send_status_message(tmux_session_name,
                     {'@type': 'server-result',