companies should not be allowed to sell shitty hardware like this. amp/dacs usually just sit on a table without much physical movement. you should contact customer support and accuse them of knowingly selling shoddy hardware because it's the second one that died on you, and see if you can get a warranty or possibly a refund. if not, try contacting your bank and give them screenshots of both your receipts for buying this item twice and maybe a bunch of screenshots from other people having issues. see if your bank will stand by your side and force a chargeback. if not, then the best you can do is sell both your amps "as is" on ebay to recoup some of the costs.