I think there is something with your transformer that caps the throughput at 64.
Well you wrote the code so you should know
From reading it last week afaics, the output is limited to 256 EU and the input is limited to 64 EU per packet. You should be able to give it 4 64 EU packets and get a 256 out, or 8 32 eu packets, but the max voltage for any individual input packet is supposed to be 64. Anything over that is supposed to trigger the overload kaboom. Err, wait... maybe the overload check was *only* done on the output being >256? Which means the stated maximum input voltage the tooltip lists is wrong; you can take an amp of 128 eu in, combine it with an amp of 32 eu and send out 160 EU. Odd.