peaky(s = adj.all) spiky - having or as if having especially high-pitched spots; "absence of peaky highs and beefed-up bass"
Derived form noun peak₁

1.  Having a peak or peaks. Tennyson. [1913 Webster]

2.  Sickly; peaked. [1913 Webster]

peaky, adj. (peakier, peakiest)
1 sickly; puny.
2 white-faced.