  We have established (a weak form of) ill-posedness for the KdV-Burgers
equation on a real line in Fourier amalgam spaces $\widehat{w}_s^{p,q}$ with
$s<-1$. The particular case $p=q=2$ recovers the result of L. Molinet and F.
Ribaud [Int. Math. Res. Not., (2002), pp. 1979-2005]. The result is new even in
Fourier Lebesgue space $\mathcal{F}L_s^q$ which corresponds to the case
$p=q(\neq 2)$ and in modulation space $M_s^{2,q}$ which corresponds to the case
$p=2,q\neq 2$.
