Revert "Fix 3"

This reverts commit e1710231ed2c610b080f413cb9bafc81f312ef8f.
Revert "Fix 2"

This reverts commit f0e113a22d1474aea46cf1d29525660c4bc9dbb6.
Revert "Tryfix #1"

This reverts commit ee5241cdd8371da58477bfbae0092a2b90d72810.
Fix a performance regression in decryption

Do not call Decrypt() for clear TS packets.

Closes #42, #43