diff --git a/src/channel/channel.cairo b/src/channel/channel.cairo
index 187cec869..138938343 100644
--- a/src/channel/channel.cairo
+++ b/src/channel/channel.cairo
@@ -21,7 +21,7 @@ impl ChannelImpl of ChannelTrait {
     }
 
     fn random_uint256_to_prover(ref self: Channel) -> u256 {
-        let mut hash_data = ArrayTrait::<u32>::new();
+        let mut hash_data = ArrayTrait::<u8>::new();
         hash_data.append_big_endian(self.digest);
         hash_data.append_big_endian(self.counter);
         self.counter += 1;
@@ -60,7 +60,7 @@ impl ChannelImpl of ChannelTrait {
     }
 
     fn read_felt_from_prover(ref self: Channel, value: felt252) {
-        let mut hash_data = ArrayTrait::<u32>::new();
+        let mut hash_data = ArrayTrait::<u8>::new();
 
         assert(self.digest.low != BoundedU128::max(), 'digest low is 2^128-1');
         hash_data.append_big_endian(self.digest + 1);
@@ -76,7 +76,7 @@ impl ChannelImpl of ChannelTrait {
     }
 
     fn read_felt_vector_from_prover(ref self: Channel, values: Span<felt252>) {
-        let mut hash_data = ArrayTrait::<u32>::new();
+        let mut hash_data = ArrayTrait::<u8>::new();
 
         assert(self.digest.low != BoundedU128::max(), 'digest low is 2^128-1');
         hash_data.append_big_endian(self.digest + 1);
@@ -95,15 +95,14 @@ impl ChannelImpl of ChannelTrait {
     }
 
     fn read_uint64_from_prover(ref self: Channel, value: u64) {
-        let mut hash_data = ArrayTrait::<u32>::new();
+        let mut hash_data = ArrayTrait::<u8>::new();
 
         assert(self.digest.low != BoundedU128::max(), 'digest low is 2^128-1');
         hash_data.append_big_endian(self.digest + 1);
 
         let low: u32 = (value % 0x100000000).try_into().unwrap();
         let high: u32 = (value / 0x100000000).try_into().unwrap();
-        hash_data.append(high.flip_endianness());
-        hash_data.append(low.flip_endianness());
+        hash_data.append_big_endian(value);
 
         self.digest = blake2s(hash_data).flip_endianness();
         self.counter = 0;