I am not 100% sure these new JACO is still waranteed by the same old JACO....my experience was (nitro) using nitro shoes (jaco brand too)...the foam is start splitting in the middle and eventually the foam will came loose or something (not sure that is the same case as you)...
That happened to more then 5 set of foams........send the JACO back and they refund me back with 5 new set of foams, never happened again.
Jaco explained there were a batch of bad foam at that period of time.....not sure your case is same as mine, contact JACO and I am sure they will send you a set after received yours, if that is not a race mistake, it is a good trouble shooting infomraiton for JACO.
P.S....had cracked rims on Nitro shoes as well, again, send those back, and got all new set from Jaco, they claimed there were a bad batch of plastic rim at that period of time as well....GQ does exactly the same thing, talk about good customer support.
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