diff --git a/mimikit/networks/sample_rnn_v2.py b/mimikit/networks/sample_rnn_v2.py
index b03f636..1d2ce77 100644
--- a/mimikit/networks/sample_rnn_v2.py
+++ b/mimikit/networks/sample_rnn_v2.py
@@ -202,7 +202,7 @@ def from_config(cls, config: "SampleRNN.Config") -> "SampleRNN":
         # only one input module supported
         spec_input_module = config.io_spec.inputs[0].module
         for i, fs in enumerate(config.frame_sizes[:-1]):
-            if isinstance(spec_input_module, FramedIO) and i == 0:  # only the top-tier has no proj of the input
+            if i == 0:  # the top-tier never has proj of the input
                 input_module = FramedIO() \
                     .set(class_size=spec_input_module.class_size, frame_size=fs, hop_length=fs).module()
                 in_dim = fs
@@ -230,9 +230,16 @@ def from_config(cls, config: "SampleRNN.Config") -> "SampleRNN":
                         else 1)
                 )]
 
-        modules = [spec_input_module.copy()
-                   .set(frame_size=config.frame_sizes[-1],
-                        hop_length=1, out_dim=h_dim, h_dim=config.embedding_dim).module()]
+        if isinstance(config.frame_sizes[-1], tuple):
+            # TODO: would be nice! needs support in batch_items, generate...
+            modules = [spec_input_module.copy()
+                       .set(frame_size=fs,
+                            hop_length=1, out_dim=h_dim, h_dim=config.embedding_dim).module()
+                       for fs in config.frame_sizes[-1]]
+        else:
+            modules = [spec_input_module.copy()
+                       .set(frame_size=config.frame_sizes[-1],
+                            hop_length=1, out_dim=h_dim, h_dim=config.embedding_dim).module()]
         input_module = ZipReduceVariables(mode=config.inputs_mode, modules=modules)
         tiers += [
             SampleRNNTier(