diff --git a/src/merge_mining_client.cpp b/src/merge_mining_client.cpp
index 828436c..4485972 100644
--- a/src/merge_mining_client.cpp
+++ b/src/merge_mining_client.cpp
@@ -23,6 +23,8 @@
 #include "merge_mining_client_tari.h"
 #endif
 
+LOG_CATEGORY(MergeMiningClient)
+
 namespace p2pool {
 
 IMergeMiningClient* IMergeMiningClient::create(p2pool* pool, const std::string& host, const std::string& wallet) noexcept
@@ -39,6 +41,7 @@ IMergeMiningClient* IMergeMiningClient::create(p2pool* pool, const std::string&
 		}
 	}
 	catch (...) {
+		LOGERR(1, "Failed to create merge mining client for " << host);
 	}
 	return nullptr;
 }
diff --git a/src/merge_mining_client_json_rpc.cpp b/src/merge_mining_client_json_rpc.cpp
index a9822ad..b1d4017 100644
--- a/src/merge_mining_client_json_rpc.cpp
+++ b/src/merge_mining_client_json_rpc.cpp
@@ -384,7 +384,7 @@ bool MergeMiningClientJSON_RPC::parse_merge_mining_submit_solution(const char* d
 	const char* status = result["status"].GetString();
 
 	// Empty string means no errors and the block was accepted
-	if (strlen(status) == 0) {
+	if (status[0] == '\0') {
 		status = "accepted";
 	}
 
diff --git a/src/merkle.cpp b/src/merkle.cpp
index 0be9008..8aaf941 100644
--- a/src/merkle.cpp
+++ b/src/merkle.cpp
@@ -259,7 +259,7 @@ root_hash get_root_from_proof(hash h, const std::vector<hash>& proof, size_t ind
 	return root_hash(h);
 }
 
-bool verify_merkle_proof(hash h, const std::vector<hash>& proof, size_t index, size_t count, const root_hash& root)
+bool verify_merkle_proof(const hash& h, const std::vector<hash>& proof, size_t index, size_t count, const root_hash& root)
 {
 	return get_root_from_proof(h, proof, index, count) == root;
 }
diff --git a/src/merkle.h b/src/merkle.h
index 77b1027..fb48b4e 100644
--- a/src/merkle.h
+++ b/src/merkle.h
@@ -26,7 +26,7 @@ bool get_merkle_proof(const std::vector<std::vector<hash>>& tree, const hash& h,
 
 root_hash get_root_from_proof(hash h, const std::vector<hash>& proof, size_t index, size_t count);
 
-bool verify_merkle_proof(hash h, const std::vector<hash>& proof, size_t index, size_t count, const root_hash& root);
+bool verify_merkle_proof(const hash& h, const std::vector<hash>& proof, size_t index, size_t count, const root_hash& root);
 bool verify_merkle_proof(hash h, const std::vector<hash>& proof, uint32_t path, const root_hash& root);
 
 uint32_t get_aux_slot(const hash &id, uint32_t nonce, uint32_t n_aux_chains);
diff --git a/src/p2pool.cpp b/src/p2pool.cpp
index 5eb0742..1acf1b2 100644
--- a/src/p2pool.cpp
+++ b/src/p2pool.cpp
@@ -564,7 +564,7 @@ void p2pool::update_aux_data(const hash& chain_id)
 			data.aux_nonce = m_auxNonce;
 		}
 		else if (find_aux_nonce(aux_id, data.aux_nonce)) {
-			m_auxId = aux_id;
+			m_auxId = std::move(aux_id);
 			m_auxNonce = data.aux_nonce;
 		}
 		else {
diff --git a/tests/src/merkle_tests.cpp b/tests/src/merkle_tests.cpp
index 53d04c8..a41e8d7 100644
--- a/tests/src/merkle_tests.cpp
+++ b/tests/src/merkle_tests.cpp
@@ -334,6 +334,8 @@ TEST(merkle, params)
 	ASSERT_EQ(PoolBlock::encode_merkle_tree_data(1, 0xFFFFFFFFU), 0xFFFFFFFF0ULL);
 	ASSERT_EQ(PoolBlock::encode_merkle_tree_data(127, 0), 0x3F6U);
 	ASSERT_EQ(PoolBlock::encode_merkle_tree_data(127, 0xFFFFFFFFU), 0x3FFFFFFFFF6ULL);
+	ASSERT_EQ(PoolBlock::encode_merkle_tree_data(256, 0), 0x7FFU);
+	ASSERT_EQ(PoolBlock::encode_merkle_tree_data(256, 0xFFFFFFFFU), 0x7FFFFFFFFFFULL);
 
 	PoolBlock b;
 	uint32_t n1, nonce1;
@@ -354,12 +356,22 @@ TEST(merkle, params)
 	b.decode_merkle_tree_data(n1, nonce1);
 	ASSERT_TRUE(n1 == 127 && nonce1 == 0xFFFFFFFFU);
 
-	for (uint32_t n_aux_chains = 1; n_aux_chains < 128; ++n_aux_chains) {
+	b.m_merkleTreeData = 0x7FFU;
+	b.decode_merkle_tree_data(n1, nonce1);
+	ASSERT_TRUE(n1 == 256 && nonce1 == 0);
+
+	b.m_merkleTreeData = 0x7FFFFFFFFFFULL;
+	b.decode_merkle_tree_data(n1, nonce1);
+	ASSERT_TRUE(n1 == 256 && nonce1 == 0xFFFFFFFFU);
+
+	for (uint32_t n_aux_chains = 1; n_aux_chains <= 256; ++n_aux_chains) {
 		for (uint32_t nonce = 1; nonce; nonce <<= 1) {
-			b.m_merkleTreeData = PoolBlock::encode_merkle_tree_data(n_aux_chains, nonce);
-			b.decode_merkle_tree_data(n1, nonce1);
-			ASSERT_EQ(n1, n_aux_chains);
-			ASSERT_EQ(nonce1, nonce);
+			for (uint32_t i = 0; i <= 1; ++i) {
+				b.m_merkleTreeData = PoolBlock::encode_merkle_tree_data(n_aux_chains, nonce - i);
+				b.decode_merkle_tree_data(n1, nonce1);
+				ASSERT_EQ(n1, n_aux_chains);
+				ASSERT_EQ(nonce1, nonce - i);
+			}
 		}
 	}
 }