Snow,
The problem may be your 127s, it may be that your radio needs a full checkup and retuning. I would start with waiting for the new receivers to come back. If that doesn't solve the problem, and assuming your 8U hasn't been in for service/module tuned in the last year, I would go there next. You can check for that issue by using someone else's transmitter, if you know someone else on 58.

Yes, the 127s and 128s are low end budget receivers. You're asking a lot from them in that type of environment. You may need to think about going to R148Df or preferably going to PCMs once you are sure all bugs are worked out of the bird.