Husk, 6 bytes

Von1Lg 

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Hooray for all ASCII solutions! Outputs 0 if the input is doublespeak, otherwise a positive integer. if you want 1 for truthy, 0 for falsey, yoi can prepend =0 to the code.

 g Group the input into lists of the same adjacent elements V Find the index of the first element that matches the predicate o Combination of the next two functions L The length n1 Is odd (bitwise AND 1)