diff --git a/pyfstat/mcmc_based_searches.py b/pyfstat/mcmc_based_searches.py
index e2836b1a7e8fff8cedef802336371d2c2a7f0c44..f16ff82554d82f251209cdb8af4d1304fdb43844 100644
--- a/pyfstat/mcmc_based_searches.py
+++ b/pyfstat/mcmc_based_searches.py
@@ -266,7 +266,7 @@ class MCMCSearch(core.BaseSearchClass):
         if test_type in ['autocorr']:
             self._get_convergence_test = self.test_autocorr_convergence
         elif test_type in ['GR']:
-            self._get_convergence_test= self.test_GR_convergence
+            self._get_convergence_test = self.test_GR_convergence
         else:
             raise ValueError('test_type {} not understood'.format(test_type))
 
@@ -282,6 +282,10 @@ class MCMCSearch(core.BaseSearchClass):
                 acors[temp, :] = emcee.autocorr.exponential_time(x)
             c = np.max(acors, axis=0)
         except emcee.autocorr.AutocorrError:
+            logging.info('Failed to calculate exponential autocorrelation')
+            c = np.zeros(self.ndim) + np.nan
+        except AttributeError:
+            logging.info('Unable to calculate exponential autocorrelation')
             c = np.zeros(self.ndim) + np.nan
 
         self.convergence_diagnosticx.append(i - self.convergence_n/2.)