HA! This just made me laugh. I took a painting workshop with this eccentric landscape painter, and his favorite catch phrase for anyone relaying an "issue" was, "Hmm. Sounds like a personal problem." BAHA HA! So immature! But I kind of love it.
Like someone would say, "Well I cant' blend more red into my green there because it will throw off the other corner". Rather than REPEAT his original advice, which was right all along, he would just say, "Hmm, sounds like a personal problem." and walk away :)
He was USED to 40 years teaching stubborn, entitled, artsy egomaniacs, who are not unlike kids!!!!
Maybe try that!
On the serious side. I'd be firmer about it. I wouldn't let my kids nag me, even if it took some discipline. I also don't think they'd get to have the spiffy electronics privileges unless they bought them themselves and acted well.