Soft truffles after dipping
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The humidty of your fridge can cause havoc with the texture of the ganache, this is why it shouldn't be refrigerated. Butter has a lower melting point than chocolate, so it will give the ganache a much softer mouthfeel. But I wouldn't call it a mistake.
You can play wit the consistency by playing with the amount of liquids you put in your ganache, less liquid= firmer ganache.
hope this helps