Hello
A few weeks ago, I bought a Raspberry pi 3 B + and a Gekkoscience 2Pac. it worked well for a short time. Then nothing. I have already updated and followed the manufacturer's instructions for installing Raspbian. Since the crash of Gekkoscience 2Pac, the cgminer always shows me that he can not find any chips.
I use this following command to start tuning with the Gekkoscience 2Pac
./cgminer -o stratum+tcp://depool.ckpool.org:3333 -u 3LdYRu3ZRRW4PbCZ9FGhbddzfGxRScCnkB -p x --suggest-diff 32 --gekko-2pac-freq 25
cgminer is connecting to your pool. That's good.
Your USB hub is one of the better ones... That's good.
If everything was working well for you, it should be no difficulty for you to push to 200MHz or more (with sufficient cooling). Not finding any chips `might' be a dead miner, BUT... Before you consider returning the 2Pac (to the vendor you purchased from) I would try this... You are running it at 25MHz. That is
extremely low for your equipment... maybe change it to 100MHz to see if you can `wake it up'. I've seen many times where these 2Pacs don't operate well if they are under-powered... 25MHz may not be asking for enough power to fuel your miner - so give 100MHz a try... if you have a USB or 12V fan to keep things cool, you won't hurt the 2Pac - even at 200MHz.
Also, look back to the first few pages of this topic. It may be that the potentiometer needs to be adjusted back to its stock position.
Also, try starting cgminer without your 2Pac plugged in. Sometimes hot-plugging a miner once cgminer is already running will be enough to get the miner started...
You have many things yet to try before declaring your 2Pac dead...
Good luck... And I hope one of these suggestions will help you.