diff --git a/tools/mtmd/clip.cpp b/tools/mtmd/clip.cpp
index b9dd5e8452..5969bf7599 100644
--- a/tools/mtmd/clip.cpp
+++ b/tools/mtmd/clip.cpp
@@ -3898,8 +3898,9 @@ struct clip_init_result clip_init(const char * fname, struct clip_context_params
 struct clip_cap clip_get_cap(const char * fname) {
     clip_cap res;
     clip_model_loader loader(fname, /* skip_tensors= */ true);
-    res.has_vision = loader.has_vision;
-    res.has_audio  = loader.has_audio;
+    res.has_vision    = loader.has_vision;
+    res.has_audio     = loader.has_audio;
+    res.has_gen_audio = loader.has_gen_audio;
     return res;
 }
 
diff --git a/tools/mtmd/clip.h b/tools/mtmd/clip.h
index a5b7137752..56c200482c 100644
--- a/tools/mtmd/clip.h
+++ b/tools/mtmd/clip.h
@@ -134,5 +134,6 @@ std::map<ggml_backend_dev_t, size_t> clip_get_mem_usage(const struct clip_ctx *
 struct clip_cap {
     bool has_vision;
     bool has_audio;
+    bool has_gen_audio;
 };
 struct clip_cap clip_get_cap(const char * fname);
diff --git a/tools/mtmd/mtmd.cpp b/tools/mtmd/mtmd.cpp
index 4063d28e07..fdef2079da 100644
--- a/tools/mtmd/mtmd.cpp
+++ b/tools/mtmd/mtmd.cpp
@@ -2510,10 +2510,11 @@ struct mtmd_caps mtmd_get_cap_from_file(const char * fname) {
         mtmd_caps cap;
         cap.inp_audio  = tmp.has_audio;
         cap.inp_vision = tmp.has_vision;
+        cap.gen_audio  = tmp.has_gen_audio;
         return cap;
     } catch (const std::exception & e) {
         LOG_ERR("%s: failed to get capabilities from file '%s': %s\n", __func__, fname, e.what());
-        return mtmd_caps{ false, false };
+        return mtmd_caps{ false, false, false };
     }
 }
 
diff --git a/tools/mtmd/mtmd.h b/tools/mtmd/mtmd.h
index 78587f3fed..084507bec6 100644
--- a/tools/mtmd/mtmd.h
+++ b/tools/mtmd/mtmd.h
@@ -337,6 +337,7 @@ MTMD_API void mtmd_log_set(ggml_log_callback log_callback, void * user_data);
 struct mtmd_caps {
     bool inp_vision;
     bool inp_audio;
+    bool gen_audio;
 };
 MTMD_API struct mtmd_caps mtmd_get_cap_from_file(const char * mmproj_fname);
 
diff --git a/tools/server/server-context.cpp b/tools/server/server-context.cpp
index 9f6490e08e..a5d1c2732a 100644
--- a/tools/server/server-context.cpp
+++ b/tools/server/server-context.cpp
@@ -42,8 +42,11 @@ constexpr int HTTP_POLLING_SECONDS = 1;
 
 static common_speculative_output_limits server_output_limits(const common_params & params) {
     if (!params.mmproj.path.empty()) {
-        // gen-audio (TTS) capability isn't known until the mmproj loads, size generously
-        return { params.n_batch, params.n_batch };
+        const auto mcaps = mtmd_get_cap_from_file(params.mmproj.path.c_str());
+        if (mcaps.gen_audio) {
+            // some TTS models decode with embeddings output for the whole batch
+            return { params.n_batch, params.n_batch };
+        }
     }
 
     if (params.embedding ||
diff --git a/tools/server/server-models.cpp b/tools/server/server-models.cpp
index 93e940951e..a292766f12 100644
--- a/tools/server/server-models.cpp
+++ b/tools/server/server-models.cpp
@@ -624,7 +624,7 @@ void server_models::load_models() {
                 /* progress      */ {},
                 /* exit_code     */ 0,
                 /* stop_timeout  */ DEFAULT_STOP_TIMEOUT,
-                /* multimodal    */ mtmd_caps{false, false},
+                /* multimodal    */ mtmd_caps{false, false, false},
                 // /* need_download */ false,
             };
             add_model(std::move(meta));
@@ -797,7 +797,7 @@ void server_models::load_models() {
                     /* progress      */ {},
                     /* exit_code     */ 0,
                     /* stop_timeout  */ DEFAULT_STOP_TIMEOUT,
-                    /* multimodal    */ mtmd_caps{false, false},
+                    /* multimodal    */ mtmd_caps{false, false, false},
                     // /* need_download */ false,
                 };
                 add_model(std::move(meta));