Incongruence-Aware Evaluation of Multimodal Speech Emotion Recognition in Audio Large Language Models
Authors: Fengji Jing, Guy Laban
Organizations: Faculty of Science, The University of Hong Kong, Hong Kong, China · Department of Industrial Engineering and Management, Ben-Gurion University of the Negev, Beer Sheva, Israel · School of Brain Sciences and Cognition, Ben-Gurion University of the Negev, Beer Sheva, Israel · Azrieli National Center for Autism and Neurodevelopment Research, Ben-Gurion University of the Negev, Beer Sheva, Israel
Voice-interactive large language models process both what a speaker says and how they say it, yet the two channels do not always agree. We ask whether that disagreement degrades speech emotion recognition. Mapping text and audio into a shared valence-arousal-dominance space, we convert the distance between them into a continuous, threshold-free incongruence score with a two-component Gaussian mixture, and validate the score against human judgement. We evaluate three audiocapable models on acted, conversational and spontaneous speech (eNTERFACE'05, MELD and CMU-MOSEI). With the model held constant across modalities, incongruence raises the odds of error whenever audio is present, in every corpus, after controlling for the ground-truth emotion and for distance in the feature space. Supervised classifiers trained on the same features behave in the opposite way, which suggests that the difficulty lies in how these models combine raw evidence rather than in the signal itself. Text-only effects are unreliable: swapping only the model that reads the transcript reverses their sign on one corpus. Rebuilding the score without the emotion lexicon reproduces the central result, and among six simpler alternatives it is the only label-free score that predicts error in all three corpora. Code, data tables and prompts are released.
Figures & tables
Fig. 1: Overview. Text and audio are mapped into a shared VAD space; their Euclidean distance is converted to a continuous incongruence probability pincon via a two-component GMM fitted on training distances. LLM predictions are evaluated stratified by pincon , and compared against VAD-feature baselines.
Fig. 2: Distributions of the extracted valence, arousal, and dominance values by modality on eNTERFACE (text from the NRC-VAD lexicon, audio from the fine-tuned wav2vec2 regressor). The two modalities occupy overlapping but distinct regions of the VAD space, and their per-utterance discrepancy is what pincon quantifies.
Corpus
T1 txt
T1 t+a
T2 txt
T2 t+a
eNTERFACE
0.0
1.4
0.5
1.5
MELD
0.0
5.5
0.0
4.9
MOSEI
15.8
14.5
13.6
14.7
TABLE I: Invalid-response rate (%) per condition (GPT-audio): responses that were unparseable or out-of-vocabulary and hence excluded.
Model
Cond.
Acc.
F1
Acc c
Acc i
OR
β
GLM-4-Voice
T1 txt
.686
.662
.722
.630
1.20
+.02
T1 t+a
.627
.530
.667
.565
0.69
−.18∗∗
T2 txt
.729
.727
.764
.674
1.36
+.14∗
T2 t+a
.720
.709
.750
.674
0.81
−.14∗
Qwen2-Audio
T1 txt
.767
.751
.767
.766
1.35
+.18∗
T1 t+a
.700
.657
.726
.660
1.27
+.15∗
TABLE II: eNTERFACE’05 (test split): overall accuracy and Macro-F1; congruent vs incongruent accuracy; and the control-adjusted logistic effect of pincon on error (all-split, with text-length and audio-duration controls). ∗p<0.05 , ∗∗p<0.01 , ∗∗∗p<0.001 . OR is the unadjusted high-versus-low incongruence odds ratio; β is the coefficient from the adjusted continuous logistic model.
Emotion
eNTERFACE
MELD
MOSEI
surprise
1.99∗∗∗ (harms)
1.15 ns
0.69 ns
disgust
0.81∗ (helps)
1.17 ns
1.42 ns
fear
0.91 ns
1.58 ns
0.55∗ (helps)
anger
1.05 ns
0.66∗∗∗ (helps)
0.68∗∗∗ (helps)
sadness
0.58∗∗∗ (helps)
0.76 ns
0.50∗∗∗ (helps)
happiness / joy
0.34 ns
1.21 ns
1.65∗∗∗ (harms)
TABLE III: Within-emotion incongruence effect: odds ratio for misclassification of high- versus low- pincon items, holding the ground-truth class fixed (pooled over all splits and all 12 LLM conditions for eNTERFACE; GPT-audio conditions for MELD and MOSEI). OR >1 = incongruence harms; OR <1 = incongruence helps. ∗p<0.05 , ∗∗∗p<0.001 ; ns = not significant.
Fig. 3: Paradigm dissociation on eNTERFACE (test split, T2 text+audio for the LLMs). Audio LLMs lose accuracy on incongruent utterances, whereas discriminative classifiers trained on the same six VAD features gain accuracy, because a larger cross-modal gap makes classes more separable. This is consistent with the harm arising during raw multimodal integration rather than from the VAD features (the baselines are supervised, however, so this is not by itself proof of mechanism).
Cond.
Acc.
F1
Acc c
Acc i
OR
β
logit p
T1 text-only
.597
.479
.605
.582
1.10
+.05
.234
T2 text-only
.606
.487
.626
.569
1.27
+.10
.022 ∗
T1 text+audio
.580
.483
.597
.549
1.21
+.10
.032 ∗
T2 text+audio
.540
.469
.560
.504
1.25
+.11
.017 ∗
TABLE IV: MELD test split using GPT-audio in all four conditions. OR is the high- versus low- pincon error odds ratio and β is the condition-wise continuous logistic coefficient. The added-audio interaction is not significant for either prompt. ∗p<0.05 .
Fig. 4: Within-emotion incongruence effect (OR of error) by corpus. Values >1 (red) mean incongruence harms recognition of that emotion; <1 (blue) mean it helps. Sadness and anger, the classes with the most characteristic prosody, are helped wherever their effect is significant; the classes that are harmed differ by corpus. (MELD has no “happiness” class; its positive label is “joy”.)
Corpus
Reader
Acc.
Adj. OR (95% CI)
eNTERFACE
gpt-5.2
.832
1.12[0.91,1.37]
gpt-audio-1.5
.818
0.78[0.63,0.97]
MELD
gpt-5.2
.594
1.03[0.94,1.13]
gpt-audio-1.5
.601
1.06[0.94,1.18]
MOSEI
gpt-5.2
.543
1.23[1.14,1.33]
gpt-audio-1.5
.536
1.24[1.14,1.35]
TABLE V: Text-only condition read by two different models, with transcripts, prompts, pincon and labels held fixed. Accuracy is materially the same; sensitivity to incongruence is not. Odds ratios come from a model fitted to the text-only condition alone, so they differ slightly from the text-only cells of Table VII , which come from the pooled model with an audio interaction.
Corpus
Modality
GPT-audio
Qwen2.5-Omni
GLM-4-Voice
MELD
text-only
1.11[1.00,1.24]
1.04[0.90,1.20]
0.99[0.87,1.13]
text+audio
1.15[1.04,1.28]
1.14[0.97,1.34]
1.07[0.94,1.22]
MOSEI
text-only
1.22[1.12,1.33]
0.95[0.79,1.14]
1.04[0.86,1.24]
text+audio
1.20[1.11,1.30]
0.96[0.79,1.17]
0.93[0.78,1.12]
TABLE VI: Cross-model incongruence effect on the extension corpora: adjusted OR of error for pincon (95% CI) from the cluster-robust model, for all three audio-LLM families. GPT-audio is on the full corpora; Qwen2.5-Omni and GLM-4-Voice on the matched stratified sample. Bold = CI excludes 1 .
Corpus
Modality
Adj. OR
95% CI
q (FDR)
eNTERFACE
text-only
0.85
[0.73,0.98]
.029
text+audio
1.25
[1.04,1.49]
.022
MOSEI
text-only
1.22
[1.12,1.33]
<.001
text+audio
1.20
[1.11,1.30]
<.001
MELD
text-only
1.11
[1.00,1.24]
.051 (ns)
text+audio
1.15
[1.04,1.28]
.017
TABLE VII: Adjusted effect of pincon on GPT-audio error from a cluster-robust logistic model per corpus (controls: prompt, ground-truth emotion, text/audio prototype distance, text length, audio duration; SEs clustered by speaker or utterance). Odds ratios with 95% CIs; q is the Benjamini–Hochberg FDR-corrected p -value across the six effects. The text+audio effect (bold) is harmful and significant in all three corpora; the text-only effects are inconsistent in sign and are model-dependent (Section V-H ).
Fig. 5: Adjusted association between pincon and error from the cluster-robust logistic model, with controls for emotion, prototype distance, length and duration (95% CIs). Circles are GPT-audio on all three corpora; triangles are Qwen2.5-Omni and diamonds GLM-4-Voice on the matched MELD and MOSEI samples. Filled markers have intervals that exclude 1 . For GPT-audio the text+audio association is positive in every corpus, while the text-only association changes sign across corpora. Qwen2.5-Omni agrees in direction on MELD ( 1.14 ) without reaching significance, and GLM-4-Voice shows no significant association, in line with its much weaker accuracy.
Corpus
Register
Text → label (VAD)
Transcript-only GPT acc
Embed. probe F1
Text-only effect
eNTERFACE’05
read, emotion-prototypical
0.733
0.818
1.00
protective
CMU-MOSEI
spontaneous monologue
0.388
0.536
0.24
present
MELD
conversational dialogue
0.188
0.601
0.27
absent
TABLE VIII: Lexical emotional transparency by three measures: a lexicon-based one (text-VAD nearest-prototype accuracy, which shares signal with pincon ) and two VAD- independent ones (transcript-only GPT accuracy, and the cross-validated macro-F1 of a linear probe on frozen all-mpnet-base-v2 sentence embeddings). All three agree that eNTERFACE is by far the most explicit. The text-only effect (last column) does not order with transparency, which is why we do not treat transparency as governing it. The embedding probe reaches a ceiling on eNTERFACE, whose closed scripted-sentence set makes the transcript trivially diagnostic.
Score
Labels
eNTERFACE
MELD
MOSEI
pincon (GMM posterior)
no
1.25∗
1.15∗
1.20∗
Euclidean distance
no
1.10
1.15∗
1.23∗
z-scored distance
no
1.37∗
1.00
1.21∗
Cosine distance
no
1.52∗
1.00
1.32∗
Valence gap
no
1.11
0.96
1.18∗
Valence-sign flip
no
1.70∗
0.91
1.31∗
TABLE IX: pincon against simpler stratifiers. Each score replaces pincon in the primary model of Table VII ; entries are GPT-audio text+audio odds ratios per standard deviation (binary flags included). ∗ 95% CI excludes 1 . “Labels” marks scores that require gold emotion labels; prototype disagreement is cross-fitted across speakers, so no utterance’s flag uses its own speaker’s labels.
Fig. 6: Convergent validity: the text+audio incongruence effect under the lexicon-based pincon (NRC lexicon + audeering audio-VAD; blue) versus a fully neural, lexicon-free pincon (EmoBank-trained text-VAD regressor + WavLM audio-VAD; orange), under the identical cluster-robust specification. Filled markers exclude OR =1 . On eNTERFACE and MOSEI the neural score reproduces the text+audio association found with the lexicon-based one; on MELD it does not, so the convergence is partial.
Corpus
Modality
Primary
WavLM
eNTERFACE
text-only
0.715[0.598,0.853]
0.827[0.708,0.966]
text+audio
1.006[0.829,1.221]
1.140[0.970,1.340]
MELD
text-only
1.046[0.955,1.146]
1.008[0.928,1.094]
text+audio
1.077[0.989,1.173]
0.889[0.786,1.005]
MOSEI
text-only
1.104[1.025,1.188]
1.140[1.059,1.227]
text+audio
1.085[1.011,1.164]
1.084[1.010,1.163]
TABLE X: Association between pincon and GPT-audio error under the primary audio-VAD extractor and an independent WavLM extractor. Entries are adjusted ORs with 95% CIs from the same reduced cluster-robust specification. Bold entries have CIs excluding 1 . Robustness is strongest on MOSEI and limited on MELD and eNTERFACE.
Corpus
Modality
N scored
N valid
invalid %
eNTERFACE
text-only
2574
2568
0.2
text+audio
2574
2537
1.4
MELD
text-only
4148
4147
0.02
text+audio
4148
3931
5.2
MOSEI
text-only
8422
7185
14.7
text+audio
8422
7195
14.6
TABLE XI: GPT-audio analysis sample sizes (pooled over the two prompts) and invalid-response rates. Invalid (non-label) outputs are negligible on eNTERFACE and MELD but frequent on MOSEI in both modalities, the audio-capable model declining to answer on roughly one seventh of those utterances; the invalid-as-error sensitivity check (Section V-K ) addresses them.
Transcript
Gold
text/audio
pincon
GPT
“You’re getting paid to work, not drink coffee!”
anger
anger/sadness
0.20
anger
“Aaaaah a cockroach!!!”
disgust
disgust/sadness
0.76
fear
“Everything was so perfect! I just don’t understand!”
sadness
sadness/sadness
0.81
sadness
“Oh no, tell me this is not true, please!”
sadness
anger/sadness
1.00
fear
TABLE XII: Illustrative eNTERFACE utterances, with the nearest-prototype emotion of each modality, pincon , and the GPT-audio prediction (T2, text+audio). Category and score capture different things: the first row has discordant prototype labels but a low score, the third concordant labels but a high one, because pincon measures distance in VAD space rather than a change of category.
Fengji Jing is with the Faculty of Science, the University of Hong Kong, Hong Kong, China.
Table 19
Guy Laban is with the Department of Industrial Engineering and Management, the School of Brain Sciences and Cognition, and the Azrieli National Center for Autism and Neurodevelopment Research, Ben-Gurion University of the Negev, Beer Sheva, Israel.
Department of Computer Science, University of Sheffield, United Kingdom · Signal Analysis and Interpretation Laboratory (SAIL), Ming Hsieh Department of Electrical and Computer Engineering, University of Southern California, Los Angeles, CA 90089, USA