After WAY too long trying to deposit a check using Digital Credit Union’s scan function, I learned a few tricks that led to success.
1. Set scanner to 300 DPI
2. If the program can’t detect the edges of the check, mark then and put a colored paper behind the check to scan. (Who thought of this second part? Sal? Kat?)
3. The biggie: do NOT use Chrome! Firefox works fine, Chrome just does not.
Jane's Lessons Learned 
Omg, i can relate. I was excited to have a new scanner for dcu deposits but it really doesnt work very well. I will try your tricks. Thanks.