CAMPAIGNERS will march to Cardiff City Hall on Saturday 29th April to demand protections to Cardiff’s grassroot music venues. Save Womanby Street (SWS) campaigners will join venue owners, musicians and politicians to meet Cardiff’s local party leaders. The campaign, launched last month, already has the backing of thousands including Cardiff MPs Jo Stevens and Kevin Brennan. It wants Cardiff Council and the Welsh Government to change planning policies to protect  music venues against noise complaints. On Saturday leaders of Cardiff…