Nope, it's fine. YOur tap water is probably 8.8 and then after it gasses out it settles down to 7.4 which is what your true PH is. I wouldn't touch it. Just be careful with doing too large a water change at once because the PH out of the tap is a lot higher than the tank's PH. I'm in a similar situation as my tap's PH is 8.4 but it settles down to 7.2 which is what my tank's PH is. I tend to err on the side of caution and put the tap water in a large tub with an air stone for a couple of hours to let the PH gas out before I put it into the tank but if you do smaller water changes 2-3x per week you should be fine.