diff --git a/src/map.rs b/src/map.rs
index af47725..416aba3 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -321,9 +321,12 @@ pub struct StreamableMap<R:BinReaderExt>{
 impl<R:BinReaderExt> StreamableMap<R>{
 	pub(crate) fn new(mut file:crate::file::File<R>)->Result<Self,Error>{
 		//assume the file seek is in the right place to start reading a map header
+		let mut f=file.as_mut();
 		//let mut f=file.block_reader(BlockId::new(0)).map_err(Error::File)?;
-		//println!("position={}",f.stream_position().unwrap());
-		let header:MapHeader=file.as_mut().read_le().map_err(Error::InvalidHeader)?;
+		println!("file header end position={}",f.stream_position().unwrap());
+		//let header:MapHeader=f.read_le().map_err(Error::InvalidHeader)?;
+		let header=read_map_header(&mut f).map_err(Error::InvalidHeader)?;
+		println!("map header end position={}",f.stream_position().unwrap());
 		let modes=header.modes.into_iter().map(Into::into).collect();
 		let attributes=header.attributes.into_iter().map(Into::into).collect();
 		let render_configs=header.render_configs.into_iter().map(Into::into).collect();