Another update;
I got it working. It turns out the problem I was having was due to how I was allocating the newPacket array. I changed to allocate a byte array of MAX_ETHER_FRAME size and it works fine now. Thanks for your help. I must say that it is refreshing to be able to post a question and get a reasonable answer instead of the usual “reading off the cue card” response that people seem to put on other forums.