Poor bass and treble.

I’ve owned a 5.1 set of Klipsch Synergy 2 (sf-2 floor standers, and a ksw-12 subwoofer) for about 10 years. I’ve always been very pleased how they sound, until I upgraded my receiver (Yamaha to-v377. Now the bass is either way too strong or way too weak. Often it’s not there when you want it (gun shots and explosions) and overbearing when you don’t want it (dialogue, and ambiance). I’ve been fiddling with settings for a long time, but can’t seem to make more than minor improvements. Any tweaking I can do or is the receiver I have just known to have anemic bass response?