diff --git a/ivas_processing_scripts/__init__.py b/ivas_processing_scripts/__init__.py
index 15424a3a36d74396fc4bbbcab3025475ace59838..abeb9f4f88971df803f1474d54c15236dcf67789 100755
--- a/ivas_processing_scripts/__init__.py
+++ b/ivas_processing_scripts/__init__.py
@@ -44,7 +44,7 @@ from ivas_processing_scripts.processing.processing import (
     preprocess,
     preprocess_2,
     preprocess_background_noise,
-    process_item,
+    process_condition,
     reorder_items_list,
 )
 from ivas_processing_scripts.utils import DirManager, apply_func_parallel
@@ -147,27 +147,21 @@ def main(args):
             # preprocess 2
             preprocess_2(cfg, logger)
 
-        # run conditions
-        for condition, out_dir, tmp_dir in zip(
-            cfg.proc_chains, cfg.out_dirs, cfg.tmp_dirs
-        ):
-            chain = condition["processes"]
-
-            logger.info(f"  Generating condition: {condition['name']}")
-
-            apply_func_parallel(
-                process_item,
-                zip(
-                    cfg.items_list,
-                    repeat(tmp_dir),
-                    repeat(out_dir),
-                    repeat(chain),
-                    repeat(logger),
-                    cfg.metadata_path,
-                ),
-                None,
-                "mp" if cfg.multiprocessing else None,
-            )
+        # attempt to parallelise either items or conditions based on test setup
+        parallelise_items = len(cfg.items_list) > len(cfg.proc_chains)
+        apply_func_parallel(
+            process_condition,
+            zip(
+                repeat(cfg),
+                cfg.proc_chains,
+                cfg.tmp_dirs,
+                cfg.out_dirs,
+                repeat(logger),
+                repeat(parallelise_items),
+            ),
+            None,
+            "mp" if (not parallelise_items and cfg.multiprocessing) else None,
+        )
 
     # copy configuration to output directory
     cfg.to_file(cfg.output_path.joinpath(f"{cfg.name}.yml"))
diff --git a/ivas_processing_scripts/generation/__init__.py b/ivas_processing_scripts/generation/__init__.py
index 8ee7c026d64269a0de0d7988b9df7ea5424a66e4..53892744063538d89de3137b14c0fe3ddd7f1b06 100755
--- a/ivas_processing_scripts/generation/__init__.py
+++ b/ivas_processing_scripts/generation/__init__.py
@@ -31,7 +31,6 @@
 #
 
 import logging
-import os
 
 import yaml
 
diff --git a/ivas_processing_scripts/processing/processing.py b/ivas_processing_scripts/processing/processing.py
index 29797295cc205b6fb5b2ad726211fba53a3d693e..23be60732fb89a39708bc74d79352d0c8f50bdb2 100755
--- a/ivas_processing_scripts/processing/processing.py
+++ b/ivas_processing_scripts/processing/processing.py
@@ -402,6 +402,44 @@ def process_item(
                 copyfile(ppm, out_meta[idx])
 
 
+def process_condition(
+    cfg: TestConfig,
+    condition: dict,
+    tmp_dir: Union[str, Path],
+    out_dir: Union[str, Path],
+    logger: logging.Logger,
+    parallelise_items: bool = False,
+):
+    chain = condition["processes"]
+
+    logger.info(f"  Generating condition: {condition['name']}")
+
+    if parallelise_items:
+        apply_func_parallel(
+            process_item,
+            zip(
+                cfg.items_list,
+                repeat(tmp_dir),
+                repeat(out_dir),
+                repeat(chain),
+                repeat(logger),
+                cfg.metadata_path,
+            ),
+            None,
+            "mp" if cfg.multiprocessing else None,
+        )
+    else:
+        for item, metadata in zip(cfg.items_list, cfg.metadata_path):
+            process_item(
+                item,
+                tmp_dir,
+                out_dir,
+                chain,
+                logger,
+                metadata,
+            )
+
+
 def remove_pre_and_postamble(
     x, out_fmt, fs, repeat_signal, preamble_len_ms, postamble_len_ms, meta, logger
 ):
@@ -464,4 +502,3 @@ def preprocess_background_noise(cfg):
     ] = output_audio
 
     return
-