diff --git a/gtsam/base/cholesky.cpp b/gtsam/base/cholesky.cpp
index 0b03e7bda..cad43381b 100644
--- a/gtsam/base/cholesky.cpp
+++ b/gtsam/base/cholesky.cpp
@@ -168,8 +168,10 @@ Eigen::LDLT<Matrix>::TranspositionType ldlPartial(Matrix& ABC, size_t nFrontal)
   ldlt.compute(ABC.block(0,0,nFrontal,nFrontal).selfadjointView<Eigen::Upper>());
 
   if(ldlt.vectorD().unaryExpr(boost::bind(less<double>(), _1, 0.0)).any()) {
-    gtsam::print(Matrix(ldlt.matrixU()), "U: ");
-    gtsam::print(Vector(ldlt.vectorD()), "D: ");
+    if(debug) {
+      gtsam::print(Matrix(ldlt.matrixU()), "U: ");
+      gtsam::print(Vector(ldlt.vectorD()), "D: ");
+    }
     throw NegativeMatrixException();
   }
 
diff --git a/gtsam/nonlinear/NonlinearOptimizer-inl.h b/gtsam/nonlinear/NonlinearOptimizer-inl.h
index 1102df92f..4e633660a 100644
--- a/gtsam/nonlinear/NonlinearOptimizer-inl.h
+++ b/gtsam/nonlinear/NonlinearOptimizer-inl.h
@@ -203,7 +203,8 @@ namespace gtsam {
 		      }
 		    }
 		  } catch(const NegativeMatrixException& e) {
-		    cout << "Negative matrix, increasing lambda" << endl;
+		    if(verbosity >= Parameters::LAMBDA)
+		      cout << "Negative matrix, increasing lambda" << endl;
 		    // Either we're not cautious, or the same lambda was worse than the current error.
 		    // The more adventurous lambda was worse too, so make lambda more conservative
 		    // and keep the same values.