diff --git a/src/SSHLibrary/abstractclient.py b/src/SSHLibrary/abstractclient.py
index 1c233f8ee..1222066ae 100644
--- a/src/SSHLibrary/abstractclient.py
+++ b/src/SSHLibrary/abstractclient.py
@@ -439,9 +439,10 @@ def _read_until(self, matcher, expected, timeout=None):
         timeout = TimeEntry(timeout) if timeout else self.config.get('timeout')
         max_time = time.time() + timeout.value
         while time.time() < max_time:
-            output += self.read_char()
+            output += self.read()
             if matcher(output):
                 return output
+            time.sleep(.00001) # Release GIL so paramiko I/O thread can run
         raise SSHClientException("No match found for '%s' in %s\nOutput:\n%s."
                                  % (expected, timeout, output))