Hi @dnnagy, sorry for the late reply.  I need sometime to debug into NNPACK to figure out why this happens. If this blocks you, you can get around with it by disabling NNPACK in the iOS build script and recompile the static libraries from source code. Here is what I did

Add CMAKE_ARGS+=("-DUSE_NNPACK=OFF") CMAKE_ARGS+=("-DUSE_XNNPACK=OFF")to build_ios.sh

Run BUILD_PYTORCH_MOBILE=1 IOS_ARCH=arm64 ./scripts/build_ios.sh

Follow the tutorial to link the static libraries in XCode

I was able to run your model above without NNPACK, and it worked fine on both of my iphonex and desktop simulator
    torch::autograd::AutoGradMode guard(false);
    NSString* path = [[NSBundle mainBundle]pathForResource:@"model.pt" ofType:@""];
    auto model = torch::jit::load(path.UTF8String);
    model.eval();
    auto input = torch::ones({16,1,1024});
    auto result = model.forward({input}).toTensor(); 
    result.print(); //[CPUFloatType [16, 64, 183]]