I'm not a clutch pro, does you clutch slip? If its only in first gear maybe its not the clutch afterall. Can't help much. I never had this problem.
Update : I recently bought a new cabin air filter. I replaced my old air filter (motor) with a new one. My brother gift to me for christmas was a fire blanket
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. So I installed it and it really help
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. Its exactly the same as echo-francis one. The 125w heater is not installed yet.