Early decision switch

Just started working and the reason why i have been hired is not met. I come with one plan that to imrovise the skill that i already have so that i can have more confidence while taking another jump from LTTS. But after joining, things went way south. Working on something that i don't have any prior experience nor i believe will be useful if i try for OEM next. If i am able to rejoin the other company's offer (which is a startup but same tech services) will it be better or should i hold my ground for quite sometime?