Wholemeal will likely be very dense. It could be that you're over-proofing the dough - how much is it expanding in the banneton? I wouldn't worry about letting it double in size - a 50% increase is enough.
@Thrustvector started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Wholemeal will likely be very dense. It could be that you're over-proofing the dough - how much is it expanding in the banneton? I wouldn't worry about letting it double in size - a 50% increase is enough.