diff --git a/cmlreaders/readers/eeg.py b/cmlreaders/readers/eeg.py
index dd9d03b..2a82a33 100644
--- a/cmlreaders/readers/eeg.py
+++ b/cmlreaders/readers/eeg.py
@@ -42,6 +42,8 @@ class EEGMetaReader(BaseCMLReader):
         df = pd.read_json(self.file_path, orient='index')
         sources_info = {}
         for k in df:
+            if any(df[k].apply(lambda x: isinstance(x, dict))):
+                continue
             v = df[k].unique()
             sources_info[k] = v[0] if len(v) == 1 else v
         sources_info['path'] = self.file_path

error reading some sources.json files
I'm running into errors when some sources.json files are being processed. The error is:

`TypeError: unhashable type: 'dict'`

Here's an example, using code from `_read_sources_json`.

```
file_path = '/protocols/r1/subjects/R1270J/experiments/TH1/sessions/0/ephys/current_processed/sources.json'
df = pd.read_json(file_path, orient='index')
sources_info = {}

for k in df:
    v = df[k].unique()
    sources_info[k] = v[0] if len(v) == 1 else v
```

The contents of that json file are formatted a little differently than others, I think. I'm finding about 8 TH subjects who have this issue. Not sure about other datasets.

```
{
  "R1270J_TH1_0_13Feb17_0058": {
    "0": {
      "data_format": "int16", 
      "n_samples": 2663545, 
      "sample_rate": 1000, 
      "source_file": "170212-1658/np1-001.ns2", 
      "start_time_ms": 1486947511412, 
      "start_time_str": "13Feb17_0058"
    }, 
    "1": {
      "data_format": "int16", 
      "n_samples": 2662535, 
      "sample_rate": 1000, 
      "source_file": "170212-1658/np2-001.ns2", 
      "start_time_ms": 1486947512417, 
      "start_time_str": "13Feb17_0058"
    }, 
    "data_format": "int16", 
    "n_samples": 2662535, 
    "sample_rate": 1000, 
    "source_file": "np1-001.ns2", 
    "start_time_ms": 1486947511412, 
    "start_time_str": "13Feb17_0058"
  }
```
diff --git a/cmlreaders/test/data/multiNSx_sources.json b/cmlreaders/test/data/multiNSx_sources.json
new file mode 100644
index 0000000..70a64e7
--- /dev/null
+++ b/cmlreaders/test/data/multiNSx_sources.json
@@ -0,0 +1,26 @@
+{
+  "R1191J_TH1_0_25Jun16_1758": {
+    "0": {
+      "data_format": "int16", 
+      "n_samples": 5256196, 
+      "sample_rate": 1000, 
+      "source_file": "160625-1358/np1-001.ns2", 
+      "start_time_ms": 1466877518277, 
+      "start_time_str": "25Jun16_1758"
+    }, 
+    "1": {
+      "data_format": "int16", 
+      "n_samples": 5256192, 
+      "sample_rate": 1000, 
+      "source_file": "160625-1358/np2-001.ns2", 
+      "start_time_ms": 1466877519275, 
+      "start_time_str": "25Jun16_1758"
+    }, 
+    "data_format": "int16", 
+    "n_samples": 5256192, 
+    "sample_rate": 1000, 
+    "source_file": "np1-001.ns2", 
+    "start_time_ms": 1466877518277, 
+    "start_time_str": "25Jun16_1758"
+  }
+}
\ No newline at end of file
diff --git a/cmlreaders/test/test_eeg.py b/cmlreaders/test/test_eeg.py
index 1695dd2..3ccfd4a 100644
--- a/cmlreaders/test/test_eeg.py
+++ b/cmlreaders/test/test_eeg.py
@@ -41,6 +41,7 @@ def events():
 class TestEEGMetaReader:
     @pytest.mark.parametrize("subject,filename,data_format,n_samples,sample_rate", [
         ("R1389J", "sources.json", "int16", 1641165, 1000),
+        ("R1191J", "multiNSx_sources.json", "int16", 5256192, 1000),
         ("TJ001", "TJ001_pyFR_params.txt", "int16", None, 400.0),
     ])
     def test_load(self, subject, filename, data_format, n_samples, sample_rate):

pip install -e .[dev]
parse_log_pytest
requirements.txt
pytest pytest-cov
apt-get update apt-get install -y gcc
3.6
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
alabaster==0.7.13
async-generator==1.10
attrs==22.2.0
Babel==2.11.0
bleach==4.1.0
cached-property==1.5.2
certifi==2021.5.30
charset-normalizer==2.0.12
-e git+https://github.com/pennmem/cmlreaders.git@ba6db8e7208903dea9573ebdbbde0a3bef3a8d4f#egg=cmlreaders
codecov==2.1.13
coverage==6.2
cycler==0.11.0
decorator==5.1.1
defusedxml==0.7.1
docutils==0.18.1
entrypoints==0.4
flake8==3.9.2
h5py==3.1.0
idna==3.10
imagesize==1.4.1
importlib-metadata==4.8.3
iniconfig==1.1.1
ipython-genutils==0.2.0
Jinja2==3.0.3
jsonschema==3.2.0
jupyter-client==7.1.2
jupyter-core==4.9.2
jupyterlab-pygments==0.1.2
kiwisolver==1.3.1
MarkupSafe==2.0.1
matplotlib==3.3.4
mccabe==0.6.1
mistune==0.8.4
mne==0.23.4
nbclient==0.5.9
nbconvert==6.0.7
nbformat==5.1.3
nbsphinx==0.8.8
nest-asyncio==1.6.0
numpy==1.19.5
packaging==21.3
pandas==1.1.5
pandocfilters==1.5.1
Pillow==8.4.0
pluggy==1.0.0
py==1.11.0
pycodestyle==2.7.0
pyflakes==2.3.1
Pygments==2.14.0
pyparsing==3.1.4
pyrsistent==0.18.0
pytest==7.0.1
pytest-cov==4.0.0
python-dateutil==2.9.0.post0
pytz==2025.2
pyzmq==25.1.2
requests==2.27.1
scipy==1.5.4
six==1.17.0
snowballstemmer==2.2.0
Sphinx==5.3.0
sphinx-rtd-theme==2.0.0
sphinxcontrib-applehelp==1.0.2
sphinxcontrib-devhelp==1.0.2
sphinxcontrib-htmlhelp==2.0.0
sphinxcontrib-jquery==4.1
sphinxcontrib-jsmath==1.0.1
sphinxcontrib-qthelp==1.0.3
sphinxcontrib-serializinghtml==1.1.5
testpath==0.6.0
tomli==1.2.3
tornado==6.1
traitlets==4.3.3
typing_extensions==4.1.1
urllib3==1.26.20
webencodings==0.5.1
zipp==3.6.0

name: cmlreaders
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2021.5.30=py36h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.3=he6710b0_2
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=21.2.2=py36h06a4308_0
  - python=3.6.13=h12debd9_1
  - readline=8.2=h5eee18b_0
  - setuptools=58.0.4=py36h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.37.1=pyhd3eb1b0_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - alabaster==0.7.13
      - async-generator==1.10
      - attrs==22.2.0
      - babel==2.11.0
      - bleach==4.1.0
      - cached-property==1.5.2
      - charset-normalizer==2.0.12
      - codecov==2.1.13
      - coverage==6.2
      - cycler==0.11.0
      - decorator==5.1.1
      - defusedxml==0.7.1
      - docutils==0.18.1
      - entrypoints==0.4
      - flake8==3.9.2
      - h5py==3.1.0
      - idna==3.10
      - imagesize==1.4.1
      - importlib-metadata==4.8.3
      - iniconfig==1.1.1
      - ipython-genutils==0.2.0
      - jinja2==3.0.3
      - jsonschema==3.2.0
      - jupyter-client==7.1.2
      - jupyter-core==4.9.2
      - jupyterlab-pygments==0.1.2
      - kiwisolver==1.3.1
      - markupsafe==2.0.1
      - matplotlib==3.3.4
      - mccabe==0.6.1
      - mistune==0.8.4
      - mne==0.23.4
      - nbclient==0.5.9
      - nbconvert==6.0.7
      - nbformat==5.1.3
      - nbsphinx==0.8.8
      - nest-asyncio==1.6.0
      - numpy==1.19.5
      - packaging==21.3
      - pandas==1.1.5
      - pandocfilters==1.5.1
      - pillow==8.4.0
      - pluggy==1.0.0
      - py==1.11.0
      - pycodestyle==2.7.0
      - pyflakes==2.3.1
      - pygments==2.14.0
      - pyparsing==3.1.4
      - pyrsistent==0.18.0
      - pytest==7.0.1
      - pytest-cov==4.0.0
      - python-dateutil==2.9.0.post0
      - pytz==2025.2
      - pyzmq==25.1.2
      - requests==2.27.1
      - scipy==1.5.4
      - six==1.17.0
      - snowballstemmer==2.2.0
      - sphinx==5.3.0
      - sphinx-rtd-theme==2.0.0
      - sphinxcontrib-applehelp==1.0.2
      - sphinxcontrib-devhelp==1.0.2
      - sphinxcontrib-htmlhelp==2.0.0
      - sphinxcontrib-jquery==4.1
      - sphinxcontrib-jsmath==1.0.1
      - sphinxcontrib-qthelp==1.0.3
      - sphinxcontrib-serializinghtml==1.1.5
      - testpath==0.6.0
      - tomli==1.2.3
      - tornado==6.1
      - traitlets==4.3.3
      - typing-extensions==4.1.1
      - urllib3==1.26.20
      - webencodings==0.5.1
      - zipp==3.6.0
prefix: /opt/conda/envs/cmlreaders

cmlreaders/test/test_eeg.py::TestEEGMetaReader::test_load[R1191J-multiNSx_sources.json-int16-5256192-1000]
cmlreaders/test/test_eeg.py::TestFileReaders::test_split_eeg_reader cmlreaders/test/test_eeg.py::TestFileReaders::test_split_eeg_reader_missing_contacts cmlreaders/test/test_eeg.py::TestFileReaders::test_ramulator_hdf5_reader_rhino[R1345D-FR1-0] cmlreaders/test/test_eeg.py::TestFileReaders::test_ramulator_hdf5_reader_rhino[R1363T-FR1-0] cmlreaders/test/test_eeg.py::TestFileReaders::test_ramulator_hdf5_reader_rhino[R1392N-PAL1-0] cmlreaders/test/test_eeg.py::TestFileReaders::test_ramulator_hdf5_reader cmlreaders/test/test_eeg.py::TestFileReaders::test_ramulator_hdf5_rereference cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_reader[R1298E-FR1-87-CH88] cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_reader[R1387E-FR1-13-CH14] cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_reader[TJ039-pyFR-14-CH15] cmlreaders/test/test_eeg.py::TestEEGReader::test_read_whole_session[R1161E] cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_reader_with_events[R1161E] cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_reader_with_events[R1387E] cmlreaders/test/test_eeg.py::TestEEGReader::test_rereference[R1384J-pairs-False-43-LS12-LS1] cmlreaders/test/test_eeg.py::TestEEGReader::test_rereference[R1111M-pairs-True-43-LPOG23-LPOG31] cmlreaders/test/test_eeg.py::TestEEGReader::test_rereference[R1111M-contacts-True-43-LPOG44] cmlreaders/test/test_eeg.py::TestEEGReader::test_rereference[R1286J-contacts-True-43-LJ16] cmlreaders/test/test_eeg.py::TestEEGReader::test_filter_channels[R1384J-ind.region-insula-10-200] cmlreaders/test/test_eeg.py::TestEEGReader::test_filter_channels[R1288P-ind.region-lateralorbitofrontal-5-200] cmlreaders/test/test_eeg.py::TestEEGReader::test_filter_channels[R1111M-ind.region-middletemporal-18-100] cmlreaders/test/test_eeg.py::TestRereference::test_rereference[RamulatorHDF5Reader-True] cmlreaders/test/test_eeg.py::TestRereference::test_rereference[RamulatorHDF5Reader-False] cmlreaders/test/test_eeg.py::TestLoadEEG::test_load_multisession[subjects0-experiments0] cmlreaders/test/test_eeg.py::TestLoadEEG::test_load_multisession[subjects1-experiments1] cmlreaders/test/test_eeg.py::TestLoadEEG::test_load_multisession[subjects2-experiments2] cmlreaders/test/test_eeg.py::TestLoadEEG::test_load_multisession[subjects3-experiments3] cmlreaders/test/test_eeg.py::TestLoadEEG::test_channel_discrepancies[R1387E-catFR5-0-120-125]
cmlreaders/test/test_eeg.py::TestEEGMetaReader::test_load[R1389J-sources.json-int16-1641165-1000] cmlreaders/test/test_eeg.py::TestEEGMetaReader::test_load[TJ001-TJ001_pyFR_params.txt-int16-None-400.0] cmlreaders/test/test_eeg.py::TestBaseEEGReader::test_include_contact[True] cmlreaders/test/test_eeg.py::TestBaseEEGReader::test_include_contact[False] cmlreaders/test/test_eeg.py::TestBaseEEGReader::test_scheme_type[/cmlreaders/cmlreaders/test/data/contacts.json-contacts] cmlreaders/test/test_eeg.py::TestBaseEEGReader::test_scheme_type[/cmlreaders/cmlreaders/test/data/pairs.json-pairs] cmlreaders/test/test_eeg.py::TestBaseEEGReader::test_scheme_type[-None] cmlreaders/test/test_eeg.py::TestFileReaders::test_npy_reader cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_absolute[TJ001-TJ001_events.mat-expected_basenames0] cmlreaders/test/test_eeg.py::TestEEGReader::test_eeg_absolute[R1389J-task_events.json-expected_basenames1] cmlreaders/test/test_eeg.py::TestRereference::test_rereference[SplitEEGReader-True] cmlreaders/test/test_eeg.py::TestLoadEEG::test_load_with_empty_events
cmlreaders/readers/eeg.py
cmlreaders/readers/eeg.py