Hi, had that same problem on my last car, a fiat panda, wasn't tracking or suspension bushes, it had a seized nsf brake caliper but after a bit work found it wasn't seized, a flexi brake pipe had collapsed internally acting like a valve, letting pressure through but not letting it release, but yours might be just a sticky caliper, usually start seizing when pads get low, new pads can push the piston back away from sticky position, well theres a few ideas to play with