It appears that i'm tripping the maxpacket part of fq_codel tho 1696 :( .

I have disabled tso gro gso on both eth0 & ppp0 as you'll see from the massive dump of hopefully useful information below (converted to pastebin since the maillist thought i was sending it a numeric url and dumped the message). 

Any light on where I've borked this would be great.