RMA request, no reply from support

Hi, i have a HDHomeRun Flex Quatro, that has stopped being able to detect channels. i emailed support and they said they would replace it and send me another one.

I have returned the broken one to the address supplied, and it has been delivered, but am not getting any replies from support. I've asked twice now for any kind of update.

How long should i expect to wait for a replacement? The initial email from support said they would "cross post me one" after receiving the tracking number, which i supplied.

RMA: 230663