diff --git a/src/calibre/ebooks/lrf/html/convert_from.py b/src/calibre/ebooks/lrf/html/convert_from.py
index 9ff749db0c..73a9a55694 100644
--- a/src/calibre/ebooks/lrf/html/convert_from.py
+++ b/src/calibre/ebooks/lrf/html/convert_from.py
@@ -778,11 +778,11 @@ class HTMLConverter(object, LoggingInterface):
         @param css: A dict
         '''
         src = tag.string if hasattr(tag, 'string') else tag
-        if len(src) > 32767:
+        if len(src) > 32760:
             pos = 0
             while pos < len(src):
-                self.add_text(src[pos:pos+32767], css, pseudo_css, force_span_use)
-                pos += 32767
+                self.add_text(src[pos:pos+32760], css, pseudo_css, force_span_use)
+                pos += 32760
             return
         src = src.replace('\r\n', '\n').replace('\r', '\n')
         
diff --git a/src/calibre/ebooks/lrf/pylrs/pylrf.py b/src/calibre/ebooks/lrf/pylrs/pylrf.py
index d0dbd4a609..02c575d0b0 100644
--- a/src/calibre/ebooks/lrf/pylrs/pylrf.py
+++ b/src/calibre/ebooks/lrf/pylrs/pylrf.py
@@ -118,7 +118,6 @@ def writeLineWidth(f, width):
 def writeUnicode(f, string, encoding):    
     if isinstance(string, str):
         string = string.decode(encoding)
-
     string = string.encode("utf-16-le")
     length = len(string)
     if length > 65535:
diff --git a/src/calibre/gui2/library.py b/src/calibre/gui2/library.py
index 525fd2aaa1..b21f27bad9 100644
--- a/src/calibre/gui2/library.py
+++ b/src/calibre/gui2/library.py
@@ -258,7 +258,10 @@ class BooksModel(QAbstractTableModel):
             for i in range(1, k):
                 ids.extend([idx-i, idx+i])
             ids = ids + [i for i in range(l, r, 1) if i not in ids]
-            ids = [self.db.id(i) for i in ids]
+            try:
+                ids = [self.db.id(i) for i in ids]
+            except IndexError:
+                return
             self.cover_cache.set_cache(ids)
 
     def current_changed(self, current, previous, emit_signal=True):