Trim a file

Hoping someone here can help me with this - I got the girlfriend a smart trainer just in time for lockdown. It works well, she likes it and she’s using it, BUT… Twice now at the end of her ride it has had sudden power spikes up to exactly 2,000W. This is obviously very for uncool, because it means her power curve is significantly more impressive than mine. Very uncool.

Less important than that, but still annoying, is that it means she can’t see what power she actually put out, because everything auto-scales and her ride gets pretty much drowned out.

I’m hoping I can prevent future spikes by moving the ANT+ receiver closer to the trainer (although it is only a bike length away as it is), but the old files will still be messing up her power curve and maximums. My question is, does anyone know if it is possible to trim the end off the file to get rid of that 2,000W spike?