The bifurcation to one-dimensional weakly subcritical periodic patterns is described by
the cubic-quintic Ginzburg-Landau equation
At = µA + Axx + i(a1|A|2Ax + a2A2Ax*) + b|A|2A - |A|4A.
These periodic patterns may in turn become unstable through one of two different
mechanisms, an Eckhaus instability or an oscillatory instability. We study the dynamics
near the instability threshold in each of these cases using the corresponding modulation
equations and compare the results with those obtained from direct numerical simulation of
the equation. We also study the stability properties and dynamical evolution of different
types of fronts present in the protosnaking region of this equation. The results provide
new predictions for the dynamical properties of generic systems in the weakly subcritical
regime.