2000 Acura Integra GSR Transmission problem



My 2000 Acura Integra GSR (w/190,500 miles) sometimes will not go into second gear when I downshift while driving. It also stops rolling in reverse when I depress the clutch. I can hear pronounced gear noise while driving. When the car is off, it cycles through all gears without a problem. I replaced the clutch in 2005, for the first time. I’m hoping it only needa a gear oil change. My research has indicated that the problem could be a throwout bearing. Can You help?