diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index d8d8710..340b04c 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -45,8 +45,8 @@ jobs:
         python-version: ['3.10', '3.11', '3.12']
         include:
           - os: ubuntu-latest
-            python-version: 3.9
-            DEPENDENCIES: matplotlib==3.3 numba==0.55.1 ray[default]==2.9
+            python-version: 3.10
+            DEPENDENCIES: matplotlib==3.8 numba==0.56.4 pyopencl==2023.1.2
             LABEL: -oldest
     steps:
       - uses: actions/checkout@v6
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 27ed305..f178f62 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -6,6 +6,20 @@ All notable changes to PyEBSDIndex will be documented in this file. The format i
 on `Keep a Changelog <https://keepachangelog.com/en/1.1.0>`_.
 
 
+0.3.9.2 (2026-03-06)
+==================
+ Added
+-----
+
+Changed
+-------
+- Python 3.10 is new minimum required python version.
+
+Fixed
+-----
+- Fixed PSO optimization for numpy 2.4 error.
+
+
 0.3.9 (2026-01-26)
 ==================
 
diff --git a/pyebsdindex/__init__.py b/pyebsdindex/__init__.py
index 52a7f0f..d709aa8 100644
--- a/pyebsdindex/__init__.py
+++ b/pyebsdindex/__init__.py
@@ -7,7 +7,7 @@
 ]
 __description__ = "Python based tool for Radon based EBSD indexing"
 __name__ = "pyebsdindex"
-__version__ = "0.3.9.1"
+__version__ = "0.3.9.2"
 
 
 # Try to import only once - also will perform check that at least one GPU is found.
diff --git a/pyebsdindex/pcopt.py b/pyebsdindex/pcopt.py
index c8bb2a8..4400e91 100644
--- a/pyebsdindex/pcopt.py
+++ b/pyebsdindex/pcopt.py
@@ -93,8 +93,7 @@ def _optfunction(PC_i, indexer=None, banddat=None):
             #average_fit /=  npoints
 
         result[q] = average_fit
-    #print(timer()-tic)
-    return result
+    return result.squeeze()
 
 
 def optimize(pats, indexer, PC0=None, batch=False):
@@ -480,7 +479,7 @@ def updateswarmbest(self, fun2opt, pool, **kwargs):
 
         #tic = timer()
         for part_i in range(self.n_particles):
-            temp = self.pos[part_i, :]
+            temp = self.pos[part_i, :].squeeze()
             val[part_i] = fun2opt(temp, **kwargs)
         #print(timer()-tic)
 
diff --git a/setup.py b/setup.py
index 3a551e0..ab6b9cc 100644
--- a/setup.py
+++ b/setup.py
@@ -29,7 +29,7 @@
         "pyopencl",
     ],
     "parallel": [
-        "ray[default]                   >= 2.9",
+        "ray[default]                   < 2.53",
     #    "pydantic                       < 2",
     ]
 }
@@ -57,7 +57,6 @@
     long_description_content_type="text/markdown",
     classifiers=[
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",