MAF 3: More interference?

So I made another attempt at measuring my progress in my pursuit of a larger aerobic base. I can't be completely certain, but I believe that I again was interrupted by some type of electronic interference.

I think the numbers began to not correlate with how I felt and the speed the treadmill was going at about mile 3 and resume to make sense midway through mile 6. As I was running mile 6, at one point my heart rate suddenly dropped about 10 bpm. Here are the numbers as they were recorded, but I'm not sure on there accuracy:

MAF 3:

1/2 (5:00) Warm up
Mile 1: 8:52
Mile 2: 9:12
Mile 3: 9:35*
Mile 4: 9:45*
Mile 5: 9:58*
Mile 6: 9:46*
Mile 7: 9:33
1/2 (5:24) Cool down

In the end, I felt pretty darn good for an 8-miler on a treadmill. Back outside tomorrow though.