Shooting a 66 inch ASL bow.  My draw length is probably 27 inches. The bow has been acting noisy, and I noticed I may have been pulling it back further. If I bend my elbow and shorten the draw length, the bow is much quieter.  What's the usual maximum draw length for this length of bow?  Any other thoughts?

String hitting arm guard?
My draw length with a longbow is about 27.5".  66" works fine.

Nope. Not using one. Good thought. . I've had that happen with other bows though.

Any 66" longbow should be good to draw 28", some quite a bit longer.  Sometimes when a bow starts being noisier than usual, it could mean it's time to change the string.

Thank you for the advice. I did change out the string. In the process did somewhat change the position of the string silencers and raised the brace height a bit. The bow is now quiet and I appreciate your advice. Would've never thought of an old string being the issue.

Also - don't be afraid of using a heavy arrow.  Never seen anything that can quiet down an ASL like a heavy arrow.  For my 60 pound ASL I shoot between an 700 and 750 grain arrow.  Whisper quiet.

Perhaps your brace height is a bit low?          Pardon, I did not notice this had already been suggested.