diff --git a/srsenb/src/phy/phy.cc b/srsenb/src/phy/phy.cc
index 442f7fa5a..85fe2a507 100644
--- a/srsenb/src/phy/phy.cc
+++ b/srsenb/src/phy/phy.cc
@@ -99,6 +99,12 @@ int phy::init(const phy_args_t&            args,
               srsran::radio_interface_phy* radio_,
               stack_interface_phy_lte*     stack_)
 {
+  if (cfg.phy_cell_cfg.size() > SRSRAN_MAX_CARRIERS) {
+    phy_log.error(
+        "Number of carriers=%zd provided above its maximum=%zd", cfg.phy_cell_cfg.size(), SRSRAN_MAX_CARRIERS);
+    return SRSRAN_ERROR;
+  }
+
   mlockall((uint32_t)MCL_CURRENT | (uint32_t)MCL_FUTURE);
 
   // Add PHY lib log.
diff --git a/srsenb/test/phy/CMakeLists.txt b/srsenb/test/phy/CMakeLists.txt
index a53b112e4..383a9e00f 100644
--- a/srsenb/test/phy/CMakeLists.txt
+++ b/srsenb/test/phy/CMakeLists.txt
@@ -52,7 +52,7 @@ add_lte_test(enb_phy_test_tm4 enb_phy_test --duration=${ENB_PHY_TEST_DURATION} -
 #  - 5 Aggregated carriers
 #  - 6 PRB
 #  - PUCCH format 3 ACK/NACK feedback mode and more than 2 ACK/NACK bits in PUSCH
-add_lte_test(enb_phy_test_tm1_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=5 --ue_cell_list=3,4,0,1,2 --ack_mode=pucch3 --cell.nof_prb=6 --tm=1)
+add_lte_test(enb_phy_test_tm1_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=6 --ue_cell_list=3,4,0,1,2 --ack_mode=pucch3 --cell.nof_prb=6 --tm=1)
 
 # Five carrier aggregation using PUCCH3:
 #  - 6 eNb cell/carrier
@@ -60,7 +60,7 @@ add_lte_test(enb_phy_test_tm1_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_D
 #  - 5 Aggregated carriers
 #  - 6 PRB
 #  - PUCCH format 3 ACK/NACK feedback mode and more than 2 ACK/NACK bits in PUSCH
-add_lte_test(enb_phy_test_tm4_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=5 --ue_cell_list=0,4,3,1,2 --ack_mode=pucch3 --cell.nof_prb=6 --tm=4)
+add_lte_test(enb_phy_test_tm4_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=6 --ue_cell_list=0,4,3,1,2 --ack_mode=pucch3 --cell.nof_prb=6 --tm=4)
 
 # Two carrier aggregation using Channel Selection:
 #  - 6 eNb cell/carrier
@@ -68,7 +68,7 @@ add_lte_test(enb_phy_test_tm4_ca_pucch3 enb_phy_test --duration=${ENB_PHY_TEST_D
 #  - 2 Aggregated carriers
 #  - 6 PRB
 #  - PUCCH format 1b with Channel selection ACK/NACK feedback mode
-add_lte_test(enb_phy_test_tm1_ca_cs enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=5 --ue_cell_list=4,3 --ack_mode=cs --cell.nof_prb=6 --tm=1)
+add_lte_test(enb_phy_test_tm1_ca_cs enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=6 --ue_cell_list=5,4 --ack_mode=cs --cell.nof_prb=6 --tm=1)
 
 # Two carrier aggregation using Channel Selection:
 #  - 6 eNb cell/carrier
@@ -76,7 +76,7 @@ add_lte_test(enb_phy_test_tm1_ca_cs enb_phy_test --duration=${ENB_PHY_TEST_DURAT
 #  - 2 Aggregated carriers
 #  - 6 PRB
 #  - PUCCH format 1b with Channel selection ACK/NACK feedback mode
-add_lte_test(enb_phy_test_tm4_ca_cs enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=5 --ue_cell_list=0,4 --ack_mode=cs --cell.nof_prb=6 --tm=4)
+add_lte_test(enb_phy_test_tm4_ca_cs enb_phy_test --duration=${ENB_PHY_TEST_DURATION} --nof_enb_cells=6 --ue_cell_list=1,5 --ack_mode=cs --cell.nof_prb=6 --tm=4)
 
 # Two carrier aggregation using Channel Selection and HO:
 #  - 3 eNb cell/carrier
diff --git a/srsenb/test/phy/enb_phy_test.cc b/srsenb/test/phy/enb_phy_test.cc
index 75a6b8366..abc656bff 100644
--- a/srsenb/test/phy/enb_phy_test.cc
+++ b/srsenb/test/phy/enb_phy_test.cc
@@ -1228,6 +1228,12 @@ public:
     phy_cfg.prach_cnfg.prach_cfg_info.prach_freq_offset = 2;
     phy_cfg.prach_cnfg.prach_cfg_info.zero_correlation_zone_cfg = 5;
 
+    /// eNb PHY initialisation instance
+    enb_phy = unique_srsenb_phy_t(new srsenb::phy(log_sink));
+  }
+
+  int init()
+  {
     // Create base UE dedicated configuration
     srsran::phy_cfg_t dedicated = {};
 
@@ -1293,11 +1299,10 @@ public:
     stack = unique_dummy_stack_t(new dummy_stack(phy_cfg, phy_rrc_cfg, args.log_level, args.rnti));
     stack->set_active_cell_list(args.ue_cell_list);
 
-    /// eNb PHY initialisation instance
-    enb_phy = unique_srsenb_phy_t(new srsenb::phy(log_sink));
-
     /// Initiate eNb PHY with the given RNTI
-    enb_phy->init(phy_args, phy_cfg, radio.get(), stack.get());
+    if (enb_phy->init(phy_args, phy_cfg, radio.get(), stack.get()) < 0) {
+      return SRSRAN_ERROR;
+    }
     enb_phy->set_config(args.rnti, phy_rrc_cfg);
     enb_phy->complete_config(args.rnti);
     enb_phy->set_activation_deactivation_scell(args.rnti, activation);
@@ -1307,6 +1312,8 @@ public:
 
     /// Configure UE with initial configuration
     ue_phy->reconfigure(phy_rrc_cfg);
+
+    return SRSRAN_SUCCESS;
   }
 
   void stop()
@@ -1457,6 +1464,14 @@ int main(int argc, char** argv)
 
   // Create Test Bench
   unique_phy_test_bench test_bench = unique_phy_test_bench(new phy_test_bench(test_args, srslog::get_default_sink()));
+  int                   err_code   = test_bench->init();
+  bool                  valid_cfg  = test_args.nof_enb_cells <= SRSRAN_MAX_CARRIERS;
+  if (not valid_cfg) {
+    // Verify that phy returns with an error if provided an invalid configuration
+    TESTASSERT(err_code != SRSRAN_SUCCESS);
+    return 0;
+  }
+  TESTASSERT(err_code == SRSRAN_SUCCESS);
 
   // Run Simulation
   for (uint32_t i = 0; i < test_args.duration; i++) {