analogWrite to pins A0 and A7 produce different outputs

My apologies, it turns out that I was mistaken.

After doing a reset()/save() and then a power cycle, pin A0 works perfectly with this command;
analogWrite(A0,0.5, {freq:1});

When I stated that a power cycle didn't help I was referring to all previous cases, where I had done a reset(), but not a save(), before cycling the power.

Interestingly I am running wifi code as well, so it could very possible be related to the wifi system.

Regards
Frank