This is not advice on what you should do, and I can't say for certain without seeing it in person, but if that were my A6 and the condition is what it appears to be (not very bad), then I would have already cleaned out the plug on the miner with some denatured alcohol, started it back up on a better supply, and monitored it carefully for a few days.
Good info on the plug/unplug cycles, looks like the el-cheapo cables aren't rated to be replugged very often at all, only 25 cycles (I assume 1 cycle = plug + unplug). I do wonder, though, under what conditions you'd be plugging/unplugging 10 times per minute.
The condition definitely does not appear very bad, but it's a mix of my OCD and bank account that I'm unsure about firing it up again. I ordered some 16ga. pci-e cables to use with my S5 and the OCZ psu's, and at the same time I ordered a 1200watt HP psu from HolyBitcoin - yea I couldn't resist a new psu before sending it away to be hosted. Figured that could be a month or more (or less, who knows) and I'll always find some use for the psu, so why not.
After I hear from Block C I'll know if I should try the new psu when it arrives or wait to have the unit professionally inspected. I will clean out the plug anyway in the mean time.
started it back up on a better supply, and monitored it carefully for a few days.
What would constitute "monitored"? As it was I would only run it when I was home and I checked on it almost every hour feeling air flow, feeling pci-e connectors for excess heat, stuff like that, which is another reason I was really surprised to find the melted plug.