Usage of Buffer in combination with a stack

Hey everybody,

I'm encountering the following problem: I'm sampling a continuous signal and then buffer 2 discrete values to a single frame(2x1). Furthermore I'd like to use a stack or queue to save the values to evaluate them to specific points of time (comparing asynchronuous signals).

Using only a single sampled signal (no buffer) there is no problem at all and I can save the discrete signal(s) until I need them. But if I try the same by the use of frames, the signal between buffer and stack/queue becomes one-dimensional and the buffer reports an error:

Error propagating outport dimensions in 'v16/Sample & Hold 1/Buffer'. An unoriented output vector and a buffer size greater than one were specified.

I'm now thinking several days about this problem but I'm anyhow not able to solve it... It should have probably something to do with the buffer.

Thanks in advance.