diff --git a/changelog.md b/changelog.md
index c943df84bf..120b77cfd3 100644
--- a/changelog.md
+++ b/changelog.md
@@ -41,6 +41,7 @@ Getting the correct TSS address for Bitcoin now requires proviidng the Bitcoin c
 
 ### Fixes
 
+* [1576](https://github.com/zeta-chain/node/pull/1576) - Fix zetaclient crash due to out of bound integer conversion and log prints.
 * [1575](https://github.com/zeta-chain/node/issues/1575) - Skip unsupported chain parameters by IsSupported flag
 * [1554](https://github.com/zeta-chain/node/pull/1554) - Screen out unconfirmed UTXOs that are not created by TSS itself
 * [1560](https://github.com/zeta-chain/node/issues/1560) - Zetaclient post evm-chain outtx hashes only when receipt is available
diff --git a/zetaclient/bitcoin_client.go b/zetaclient/bitcoin_client.go
index a316e3b4ac..a82e3a44cb 100644
--- a/zetaclient/bitcoin_client.go
+++ b/zetaclient/bitcoin_client.go
@@ -1326,7 +1326,7 @@ func (ob *BitcoinChainClient) LoadLastBlock() error {
 	if ob.chain.ChainId == 18444 { // bitcoin regtest: start from block 100
 		ob.SetLastBlockHeightScanned(100)
 	}
-	ob.logger.ChainLogger.Info().Msgf("%s: start scanning from block %d", ob.chain.String(), ob.lastBlock)
+	ob.logger.ChainLogger.Info().Msgf("%s: start scanning from block %d", ob.chain.String(), ob.GetLastBlockHeightScanned())
 
 	return nil
 }
diff --git a/zetaclient/zetacore_observer.go b/zetaclient/zetacore_observer.go
index 51078aefd2..aff055c74f 100644
--- a/zetaclient/zetacore_observer.go
+++ b/zetaclient/zetacore_observer.go
@@ -2,6 +2,7 @@ package zetaclient
 
 import (
 	"fmt"
+	"math"
 	"strings"
 	"time"
 
@@ -158,7 +159,7 @@ func (co *CoreObserver) startCctxScheduler() {
 						co.logger.ZetaChainWatcher.Error().Err(err).Msgf("couldn't get operator balance")
 					} else {
 						diff := co.lastOperatorBalance.Sub(balance)
-						if diff.GT(sdkmath.NewInt(0)) {
+						if diff.GT(sdkmath.NewInt(0)) && diff.LT(sdkmath.NewInt(math.MaxInt64)) {
 							co.ts.AddFeeEntry(bn, diff.Int64())
 							co.lastOperatorBalance = balance
 						}
@@ -355,7 +356,7 @@ func (co *CoreObserver) getUpdatedChainOb(chainID int64) (ChainClient, error) {
 	curParams := chainOb.GetChainParams()
 	if common.IsEVMChain(chainID) {
 		evmCfg, found := co.cfg.GetEVMConfig(chainID)
-		if found && curParams != evmCfg.ChainParams {
+		if found && curParams.String() != evmCfg.ChainParams.String() {
 			chainOb.SetChainParams(evmCfg.ChainParams)
 			co.logger.ZetaChainWatcher.Info().Msgf(
 				"updated chain params for chainID %d, new params: %v",
@@ -365,7 +366,7 @@ func (co *CoreObserver) getUpdatedChainOb(chainID int64) (ChainClient, error) {
 		}
 	} else if common.IsBitcoinChain(chainID) {
 		_, btcCfg, found := co.cfg.GetBTCConfig()
-		if found && curParams != btcCfg.ChainParams {
+		if found && curParams.String() != btcCfg.ChainParams.String() {
 			chainOb.SetChainParams(btcCfg.ChainParams)
 			co.logger.ZetaChainWatcher.Info().Msgf(
 				"updated chain params for Bitcoin, new params: %v",