diff --git a/src/ot-based/ot-psi.cpp b/src/ot-based/ot-psi.cpp
index f1c6e61..4c2f814 100644
--- a/src/ot-based/ot-psi.cpp
+++ b/src/ot-based/ot-psi.cpp
@@ -660,7 +660,7 @@ void InitOTReceiver(uint8_t* keyMtx, CSocket sock, crypto* crypt)
 	uint8_t* pBuf = (uint8_t*) malloc(crypt->get_hash_bytes() * numbaseOTs * 2);
 	bot->Sender(2, numbaseOTs, sock, pBuf);
 
-#ifdef AES256_HASH2
+#ifdef AES256_HASH
 	//Key expansion
 	uint8_t* pBufIdx = pBuf;
 	for(uint32_t i=0; i<numbaseOTs; i++ )
diff --git a/src/util/ot/ot-extension-1oon-ecc.cpp b/src/util/ot/ot-extension-1oon-ecc.cpp
index 8c972ac..67750b8 100644
--- a/src/util/ot/ot-extension-1oon-ecc.cpp
+++ b/src/util/ot/ot-extension-1oon-ecc.cpp
@@ -205,12 +205,21 @@ void OTExtension1ooNECCReceiver::GenerateChoiceCodes(CBitVector& choicecodes, CB
 
 void OTExtension1ooNECCReceiver::BuildMatrices(CBitVector& T, CBitVector& SndBuf, uint32_t numblocks, uint32_t ctr, uint8_t* ctr_buf)
 {
-	uint32_t* counter = (uint32_t*) ctr_buf;
-	uint32_t tempctr = (*counter);
+	uint64_t* counter = (uint64_t*) ctr_buf;
+	uint64_t tempctr = (*counter);
 
 	uint8_t* Tptr = T.GetArr();
 	uint8_t* sndbufptr = SndBuf.GetArr();
 
+
+#ifdef AES256_HASH
+	//first prg output written to tptr
+	intrin_sequential_gen_rnd8(ctr_buf, tempctr, Tptr, (int) 2*numblocks, (int) m_nCodeWordBits, m_vKeySeedMtx);
+
+	//second prg output written to snd buffer
+	intrin_sequential_gen_rnd8(ctr_buf, tempctr, sndbufptr, (int) 2*numblocks, (int) m_nCodeWordBits, m_vKeySeedMtx+m_nCodeWordBits);
+
+#else
 	//cout << "Numblocks = " << numblocks << endl;
 	for(uint32_t k = 0; k < m_nCodeWordBits; k++)
 	{
@@ -240,6 +249,7 @@ void OTExtension1ooNECCReceiver::BuildMatrices(CBitVector& T, CBitVector& SndBuf
 		cout << endl;
 #endif
 	}
+#endif
 	SndBuf.XORBytes(T.GetArr(), (uint32_t) 0, m_nCodeWordBytes*numblocks*m_nCodeWordBits);
 }
 
diff --git a/src/util/ot/ot-extension.cpp b/src/util/ot/ot-extension.cpp
index a86ba26..287ea65 100644
--- a/src/util/ot/ot-extension.cpp
+++ b/src/util/ot/ot-extension.cpp
@@ -196,6 +196,10 @@ void OTExtensionReceiver::BuildMatrices(CBitVector& T, CBitVector& SndBuf, uint3
 	uint8_t* Tptr = T.GetArr();
 	uint8_t* sndbufptr = SndBuf.GetArr();
 	uint32_t ctrbyte = ctr/8;
+#ifdef AES256_HASH
+	cerr << "Not supported with AES256 HASH enabled. Exiting." << endl;
+	exit(0);
+#else
 	for(uint32_t k = 0; k < m_nSymSecParam; k++)
 	{
 		(*counter) = tempctr;
@@ -211,6 +215,7 @@ void OTExtensionReceiver::BuildMatrices(CBitVector& T, CBitVector& SndBuf, uint3
 		}
 		SndBuf.XORBytesReverse(m_nChoices.GetArr()+ctrbyte, k*OTEXT_BLOCK_SIZE_BYTES * numblocks, OTEXT_BLOCK_SIZE_BYTES * numblocks);
 	}
+#endif
 	SndBuf.XORBytes(T.GetArr(), (uint32_t) 0, OTEXT_BLOCK_SIZE_BYTES*numblocks*m_nSymSecParam);
 }
 
@@ -575,7 +580,7 @@ void OTExtensionSender::BuildQMatrix(CBitVector& T, CBitVector& RcvBuf, uint32_t
 	uint32_t* counter = (uint32_t*) ctr_buf;
 	uint32_t tempctr = *counter;
 #ifdef AES256_HASH
-	cerr << "Not supported atm. Exiting." << endl;
+	cerr << "Not supported with AES256 HASH enabled. Exiting." << endl;
 	exit(0);
 #else
 	for (uint32_t k = 0; k < m_nSymSecParam; k++, rcvbufptr += (OTEXT_BLOCK_SIZE_BYTES * numblocks))
diff --git a/src/util/ot/ot-extension.h b/src/util/ot/ot-extension.h
index f79244a..36de2fd 100644
--- a/src/util/ot/ot-extension.h
+++ b/src/util/ot/ot-extension.h
@@ -210,8 +210,13 @@ class OTExtensionReceiver {
 
 
 		m_nCounter = 0;
+#ifdef AES256_HASH
+		m_vKeySeedMtx = (ROUND_KEYS*) malloc(sizeof(ROUND_KEYS) * nbaseOTs * nSndVals);
+		intrin_sequential_ks4(m_vKeySeedMtx, keybytes, (int) nbaseOTs * nSndVals);
+#else
 		m_vKeySeedMtx = (AES_KEY_CTX*) malloc(sizeof(AES_KEY_CTX) * nbaseOTs * nSndVals);
 		InitAESKey(m_vKeySeedMtx, keybytes, nbaseOTs * nSndVals);
+#endif
 
 		m_nSeed = (uint8_t*) malloc(sizeof(AES_BYTES)); //
 		m_cCrypto->gen_rnd(m_nSeed, AES_BYTES);//seed;
@@ -252,7 +257,11 @@ class OTExtensionReceiver {
   	CBitVector m_vTempOTMasks;
   	uint8_t* m_nSeed;
   	MaskingFunction* m_fMaskFct;
+#ifdef AES256_HASH
+  	ROUND_KEYS* m_vKeySeedMtx;
+#else
   	AES_KEY_CTX* m_vKeySeedMtx;
+#endif
   	crypto* m_cCrypto;
   	CLock* m_lRcvLock;
 #ifdef FIXED_KEY_AES_HASHING