diff --git a/qa/rpc-tests/dip4-coinbasemerkleroots.py b/qa/rpc-tests/dip4-coinbasemerkleroots.py
index 2cd41ddb337e4..66fcf01f56a5b 100755
--- a/qa/rpc-tests/dip4-coinbasemerkleroots.py
+++ b/qa/rpc-tests/dip4-coinbasemerkleroots.py
@@ -84,11 +84,13 @@ def run_test(self):
         #############################
         # Now start testing quorum commitment merkle roots
 
-        height = self.nodes[0].getblockcount()
+        self.nodes[0].generate(1)
+        oldhash = self.nodes[0].getbestblockhash()
         # Test DIP8 activation once with a pre-existing quorum and once without (we don't know in which order it will activate on mainnet)
         self.test_dip8_quorum_merkle_root_activation(True)
         for n in self.nodes:
-            n.invalidateblock(n.getblockhash(height + 1))
+            n.invalidateblock(oldhash)
+        self.sync_all()
         first_quorum = self.test_dip8_quorum_merkle_root_activation(False)
 
         self.nodes[0].spork("SPORK_17_QUORUM_DKG_ENABLED", 0)
@@ -252,6 +254,7 @@ def test_dip8_quorum_merkle_root_activation(self, with_initial_quorum):
 
         while self.nodes[0].getblockchaininfo()["bip9_softforks"]["dip0008"]["status"] != "active":
             self.nodes[0].generate(4)
+            self.sync_all()
         self.nodes[0].generate(1)
         sync_blocks(self.nodes)
 
diff --git a/src/miner.cpp b/src/miner.cpp
index 0c21b0f6c9b26..2acd9f42dd3e2 100644
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -221,11 +221,11 @@ std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock(const CScript& sc
 
         CValidationState state;
         if (!CalcCbTxMerkleRootMNList(*pblock, pindexPrev, cbTx.merkleRootMNList, state)) {
-            throw std::runtime_error(strprintf("%s: CalcSMLMerkleRootForNewBlock failed: %s", __func__, FormatStateMessage(state)));
+            throw std::runtime_error(strprintf("%s: CalcCbTxMerkleRootMNList failed: %s", __func__, FormatStateMessage(state)));
         }
         if (fDIP0008Active_context) {
             if (!CalcCbTxMerkleRootQuorums(*pblock, pindexPrev, cbTx.merkleRootQuorums, state)) {
-                throw std::runtime_error(strprintf("%s: CalcSMLMerkleRootForNewBlock failed: %s", __func__, FormatStateMessage(state)));
+                throw std::runtime_error(strprintf("%s: CalcCbTxMerkleRootQuorums failed: %s", __func__, FormatStateMessage(state)));
             }
         }